Shoe Lasts For Use With Conformable Booties, Shoe Inserts, Footwear Assemblies and Waterproof Breathable Socks

ABSTRACT

Waterproof, breathable socks, booties, shoe inserts, and footwear assemblies containing the shoe inserts are provided. The booties and shoe inserts include a laminate of a seamless ePTFE membrane and at least one textile. The bootie is conformable over a range of sizes and shoe shapes, and may be shaped to fit numerous sizes and shapes of asymmetrical shoe lasts. The bootie may shrink to fit, or, alternatively, be stretched to fit, an asymmetrical last having a desired size to form a shoe insert. Such a conformable bootie eliminates the need to have multiple sizes of shoe inserts correlating to particular shoe sizes. In embodiments where the ePTFE is seamless and continuous, the shoe insert eliminates the need for a waterproof seam tape, which is conventionally used to make shoe inserts waterproof. Methods of forming the socks, booties, and shoe inserts are also provided. Unique lasts and sock constructions are also provided.

FIELD OF THE INVENTION

The present invention relates generally to unique shoe lasts suitablefor use with conformable booties, shoe inserts, footwear assemblies andwaterproof, breathable socks that are conformable over a range of shoesizes. Shoe lasts for use with conformable booties and shoe insertsincorporating booties, and methods of making conformable booties andshoe inserts are provided. Shoe lasts for use with footwear assembliesand waterproof, breathable socks are also provided.

BACKGROUND OF THE INVENTION

Waterproof, breathable footwear is typically formed of an upper materialwhich is both air permeable and water permeable. The outer layer of theupper material may be leather and/or a textile fabric. Waterproofness isachieved through the use of a waterproof, water-vapor permeablefunctional material that is arranged within the shoe. In the footwearart, materials which are both waterproof and water vapor permeable arecommonly referred to as “functional” materials. The functional layer maybe made of an expanded polytetrafluoroethylene (ePTFE) materialavailable from W. L. Gore and Associates, Inc., Elkton, Md., under thetradename GORE-TEX®. The expanded PTFE is characterized as having adensity less than 2.0 g/cm³. Other functional materials have also beendeveloped and are well known in the art.

It is difficult to sew the functional layer directly to the upper and/orsole material of the footwear. In addition, the functional layer becomespermeable to water when it is pierced during the sewing process. It istherefore common to provide the footwear with a shoe insert containingthe functional layer. The shoe insert incorporates several pieces of alaminate that includes the functional layer and a textile material whichare assembled and joined to produce an insert that includes laminatepanels joined by seams in a manner to have generally the shape of afoot. A waterproof joining process may be accomplished by sewing theindividual pieces together and sealing the seams with a superimposedadhesive or sealing tape that is applied to the seam by a bonding orwelding process.

The shoe insert is generally attached within the footwear such that theupper end of the shoe insert is connected with the upper end of thefootwear by sewing or by an adhesive. The sole portion of the shoeinsert is held stationary between the outsole and the insole of thefootwear, usually by adhesive bonding over the entire surface.

One problem that often results when forming such waterproof, breathablefootwear is that the insertion of the shoe insert often results in apoor fitting shoe (i.e., the shoe insert has a different fit (shape orsize) to that of the already sized upper) and/or poor attachment betweenthe shoe insert and the shoe upper material, which results, among otherthings, in a less than desirable appearance of the inside of thefootwear (i.e., the shoe insert appears wrinkled or pulls away from theupper).

An additional problem is that because of the multiple laminate pieces orpanels needed for manufacturing an article of waterproof footwear,flexibility may be severely compromised. A further problem is thatsealing the seamed portions of the shoe insert to make the shoewaterproof may compromise the breathability and flexibility of the shoeand contribute to the poor fit of the shoe insert.

Thus, there remains a need in the art for a shoe insert that closelyconforms to the inside of the shoe, is both waterproof and breathable,and is comfortable to wear.

There further remains a need for unique shoe lasts for making such shoeinserts, booties, socks, finished shoes and other such footwearassemblies.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide unique shoe lastssuitable for use with shoe inserts, booties, and other footwearassemblies for waterproof, breathable constructions that are conformableover a range of shoe sizes, as well as for forming the resulting shoestherefrom. The lasts may be used with conformable polymer materials andlaminates, including materials such as PTFE, urethanes, and othersuitable material compositions which are capable of being stretched andformed over a shoe last, such as described in the non-limitingalternative material embodiments described herein.

In one alternative embodiment of a bootie suitable for use incombination with lasts of the present invention, a bootie that containsa laminate including a conformed ePTFE membrane, a first textile, and,optionally, a second textile. The first textile may form an interiorportion of the bootie and the second textile may form an exteriorportion of the bootie. The textile is not particularly limited as longas the textile possesses at least some elastic properties. In at leastsome exemplary embodiments, the conformed ePTFE membrane is seamless. Inexemplary embodiments, the first and/or second textile is a sock, whichmay be tubular in shape. Additionally, the sock may contain heel and/ortoe reinforcements. The inclusion of heel and toe reinforcements resultsin the bootie having a more defined, foot-like shape, which may beself-supporting. In addition, in exemplary embodiments, the conformedePTFE membrane has a thickness variation from a first location in thebootie to a second location in the bootie of at least 1.2:1. Also, thebootie is free, or substantially free, of wrinkles. The bootie has agenerally symmetrical shape. In one embodiment, the ePTFE membrane has adensity greater than or equal to about 2.0 g/cm³, which renders thebootie non-breathable but provides the wearer protection from anaggressive environment.

It is also an object of the present invention to provide a last for ashoe insert that includes a laminate that includes (1) a seamless,shaped ePTFE membrane and (2) a textile positioned on one side of theshaped ePTFE membrane. A second textile may be provided on a second sideof the shaped ePTFE membrane opposing the textile. The textiles may be aknitted textile tube, a woven textile tube, a tubular sock, or a sockhaving reinforced heel and/or toe region(s). In addition, the textilepossesses at least some elastic properties. The ePTFE membrane has athickness variation from a first location in the shoe insert to a secondlocation in the shoe insert of at least 1.2:1. Additionally, the shapedePTFE membrane may have thereon a coating, such as an oleophobic coatingand/or an abrasion resistant coating. The shoe insert has generally theshape of an asymmetrical last.

It is another object of the present invention to provide a last for afootwear article that includes a laminate that includes (1) an upperportion, (2) a shoe insert adjacent to with the upper portion, and (3) asole portion adjacent to with the upper portion and the shoe insert. Theshoe insert includes a seamless, shaped ePTFE membrane, a first textileaffixed to one side of the ePTFE membrane, and optionally, a secondtextile affixed to a second side of the ePTFE membrane. The shaped ePTFEmembrane may have a thickness variation from a first location in theshoe insert to a second location in the shoe insert of at least 1.2:1.The shoe insert may be affixed to the upper portion and/or sole portionof the footwear article or, alternatively, the shoe insert may beremovable. There are substantially no air gaps between the upper portionof the footwear article and the shoe insert. Footwear articles includingthe shoe insert do not demonstrate leaking when filled with water andcentrifuged for 30 minutes, thus passing the Centrifuge WaterproofnessTest described herein. A polymeric overlay may be positioned on the shoeinsert to provide additional cushioning, stability, and/or support. Theinclusion of polymeric overlays may permit the “overlayed” shoe insertto be worn in an indoor or outdoor environment without being part of ashoe.

It is yet another object of the present invention to provide a last fora waterproof sock that includes a laminate that includes (1) a conformedePTFE membrane and (2) a first elastic textile affixed to a first sideof the conformed ePTFE membrane. The conformed ePTFE membrane has athickness variation from a first location in the waterproof sock to asecond location in the waterproof sock of at least 1.2:1. A secondelastic textile may be affixed to a second side of the conformed ePTFEmembrane. The textile(s) selection is not particularly limited so longas the textile possesses at least some elastic properties. In at leastone embodiment, the textile(s) may be a textile tube, a tubular sock, ora conventional sock with reinforced heel and/or toe regions. Thewaterproof sock is formed on a symmetrical last, and as a result, thewaterproof sock has a generally symmetrical shape. The waterproof sockdoes not demonstrate leaking when filled with water and centrifuged for15 minutes, thus passing the Centrifuge Waterproofness Test describedherein. In one embodiment, the ePTFE membrane is densified such that theePTFE membrane has a density greater than or equal to about 2.0 g/cm³,which renders the sock non-breathable but provides the wearer protectionfrom an aggressive environment. In a further alternative embodiment, ashaped waterproof sock may be formed, or shaped, with the application ofheat (e.g., in a conventional oven) on a conventional asymmetrical lastor on a last of the present invention, as described in more detailherein, to provide the shaped waterproof, breathable sock.

It is a further object of the present invention to provide a method offorming a shoe insert that includes (1) applying an adhesive to a firstside of a textile to form a first composite, (2) positioning the firstcomposite on a symmetrical last of the present invention with theadhesive facing outwardly and away from the symmetrical last, (3)stretching a conformable ePTFE tape having an extensibility of at least1.5× in at least one direction over the first composite to form a secondcomposite that includes a conformed ePTFE membrane, the adhesive, andthe textile, (4) heating the second composite and the symmetrical lastto a temperature from about 50° C. to about 200° C. to form a bootie,(5) placing the bootie on an asymmetrical last, as described in moredetail herein, and (6) heating the bootie and the asymmetrical last to atemperature from about 50° C. to about 200° C. to form a shoe insert.The shoe insert may be cooled before removing it from the asymmetricallast. In some embodiments, the bootie and/or shoe insert may be heatedto a temperature from about 340° C. to about 375° C. to amorphously lockthe ePTFE membrane. The stretching step may include (1) positioning theconformable ePTFE tape over the symmetrical last and (2) rotating thesymmetrical last through the conformable ePTFE tape to form the secondcomposite. In the second heating step, the bootie shrinks to fit theasymmetrical last. In an alternative embodiment, the bootie may be madeto be somewhat smaller than the asymmetrical last and the bootie isstretched to fit over the asymmetrical last. In some embodiments, theePTFE membrane may have a thickness variation from a first location inthe shoe insert to a second location in the shoe insert of at least1.2:1.

It is also an object of the present invention to provide a method offorming a shoe insert that includes (1) applying a first adhesive to afirst side of a first textile to form a first composite, (2) positioningthe first composite on a symmetrical last with the first adhesive facingoutwardly and away from the symmetrical last, (3) stretching aconformable ePTFE tape having an extensibility of at least 1.5× in atleast one direction over the first composite to form a second compositecomprising a conformed ePTFE membrane, the first adhesive, and the firsttextile, (4) positioning a second textile having thereon a secondadhesive on the second composite such that the second adhesive islocated on the ePTFE membrane to form a third composite, (5) heating thethird composite and the symmetrical last to a temperature from about 50°C. to about 200° C. to form a bootie, (6) placing the bootie on anasymmetrical last, and (7) heating the bootie and the asymmetrical lastto a temperature from about 50° C. to about 200° C. to form a shoeinsert. The shoe insert may be cooled before removing the shoe insertfrom the asymmetrical last. In some embodiments, the bootie and/or shoeinsert may be heated to a temperature from about 340° C. to about 375°C. to amorphously lock the ePTFE membrane. As noted earlier herein, insome embodiments, the shoe insert may be seamless. The ePTFE membranemay have a thickness variation from a first location in the shoe insertto a second location in the shoe insert of at least 1.2:1. Thestretching step may include (1) positioning the ePTFE tape over thesymmetrical last and (2) rotating the symmetrical last through the ePTFEtape to form the second composite. Alternatively, the bootie may be madeto be somewhat smaller than the asymmetrical last and the bootie isstretched to fit over the asymmetrical last.

It is another object of the present invention to provide a method offorming a bootie that includes (1) applying an adhesive to a first sideof a textile to form a composite, (2) positioning the composite on asymmetrical last with the adhesive facing outwardly and away from thesymmetrical last, and (3) stretching a conformable ePTFE tape having anextensibility of at least 1.5× in at least one direction over thecomposite and the symmetrical last to form a bootie. The bootie is thusformed of a conformed ePTFE membrane, an adhesive, and a textile. Insome embodiments, the bootie may be heated to a temperature from about340° C. to about 375° C. to amorphously lock the ePTFE membrane. Thestretching step may include positioning the ePTFE tape over thesymmetrical last and rotating the symmetrical last through the ePTFEtape. In other embodiments, the bootie is stretched over theasymmetrical last.

It is yet another object of the present invention to provide a method offorming a shoe insert that includes (1) applying an adhesive on one of afirst textile or a side of a conformable ePTFE tape having anextensibility of at least 1.5× in at least one direction, (2)positioning the textile on a symmetrical last, (3) stretching theconformable ePTFE tape over the textile to form a first composite, (4)positioning a second composite including a second adhesive on a secondtextile on the first composite such that the second adhesive ispositioned on the ePTFE membrane to form a bootie, (5) placing thebootie on an asymmetrical last, and (5) heating the bootie and theasymmetrical last to a temperature from about 50° C. to about 200° C. toform the shoe insert. The stretching step may include rotating thesymmetrical last through the ePTFE tape. The placing step may includestretching the bootie over the asymmetrical last. The first and secondtextiles may be a knitted textile tube, a woven textile tube, a tubularsock, or a formed sock having heel and/or toe reinforcements. The shoeinsert may be self-supporting, such as, for example when the textile isa formed sock having heel and toe reinforcements.

It is also an object of the invention to provide a method of forming abootie that includes (1) applying an adhesive on a side of a firsttextile or a side of a conformable ePTFE tape having an extensibility ofat least 1.5× in at least one direction, (2) positioning the textile ona symmetrical last, (3) stretching the conformable ePTFE tape over thetextile and symmetrical last to form a first composite, (4) positioninga second composite comprising a second adhesive on a second textile onthe first composite such that the second adhesive is positioned on theePTFE membrane to form a bootie, and (5) heating the bootie to atemperature from about 50° C. to about 200° C. In some embodiments, thebootie is heated to a temperature from about 340° C. to about 375° C. toamorphously lock the ePTFE membrane. The bootie has a generallysymmetrical shape, and may be breathable over its entirety. In at leastone embodiment, the ePTFE membrane has a density greater than 2.0 g/cm³.The densified ePTFE provides protection against aggressive environments.

It is a further object of the present invention to provide a bootie thatis formed of a conformed ePTFE membrane and no textile. The conformedePTFE membrane may have thereon a coating, such as an oleophobic coatingand/or an abrasion resistant coating. Additionally, the conformed ePTFEmembrane has a thickness variation from a first location in the bootieto a second location in the bootie of at least 1.2:1. The bootie may beformed by stretching a conformable ePTFE tape over a symmetrical last ina single step. The bootie has a shape substantially similar to thesymmetrical last. In addition, the bootie may be heated to a temperaturefrom about 50° C. to about 200° C. to reduce the ability of theconformed ePTFE membrane to further stretch and/or to deform. The bootiemay also, or alternatively, be heated to a temperature from about 340°C. to about 375° C. to amorphously lock the conformed ePTFE membrane. Inone embodiment, the conformed ePTFE membrane has a density greater thanor equal to about 2.0 g/cm³, which renders the bootie non-breathable butprovides the wearer protection from an aggressive environment.

It is another object of the present invention to provide a shoe insertthat is formed of a shaped ePTFE membrane and no textile. The shapedePTFE membrane may have at least one coating layer thereon, such as, butnot limited to, an abrasion resistant coating and/or an oleophobiccoating. In one embodiment, the shaped ePTFE membrane has an abrasionresistant coating on at least one of an inner surface of the shoe insertand an outer surface of the shoe insert. The shoe insert may be formedin a one step process whereby a conformable ePTFE tape is stretched overan asymmetrical last. The shoe insert has a shape substantially similarto the asymmetrical last. The shoe insert may be heated to a temperaturefrom about 50° C. to about 200° C. to reduce the ability of theconformed ePTFE membrane to further stretch and/or to deform.Additionally, the shaped ePTFE membrane may be amorphously locked. Inone embodiment, the ePTFE membrane has a density greater than or equalto about 2.0 g/cm³, which renders the shoe insert non-breathable butprovides the wearer protection from an aggressive environment. In afurther embodiment, the shoe insert has a polymeric overlay attachedthereto to provide additional cushioning, stability, and/or support.

It is a further object of the present invention to provide a shoe insertformed of a seamless, conformed ePTFE membrane. The shoe insert may beformed by stretching a conformable ePTFE tape over a symmetrical last ofthe invention. The shoe insert may be heated to a temperature from about340° C. to about 375° C. to amorphously lock the conformed ePTFEmembrane. The conformed ePTFE membrane has a thickness variation from afirst location in the shoe insert to a second location in the shoeinsert of at least 1.2:1, The shoe insert may be breathable over itsentirety. Additionally, the shoe insert may be both waterproof andbreathable. In at least one embodiment, the shoe insert does not containa textile and has a shape substantially similar to the symmetrical last.

It is yet another object of the present invention to provide asymmetrical shoe last that contains a first portion and a second portionwhere the first and second portions are substantial mirror images ofeach other across a generally central axis. The symmetrical shoe lastmay be formed to have different shapes and/or sizes depending on the enduse of the article. In addition, the symmetrical design of the shoe lastcan be changed to allow for additional shoe construction features, suchas additional tongue gusset materials, size, width, shoe types, etc, solong as the symmetry along a centrally located axis remains intact.Thus, the symmetrical last can be customized to meet a variety of shapesand sizes to meet desired end uses.

A typical shoe last used in the making of shoes is shown in FIG. 21A.The shoe last shape represents the shoe after closure of the shoe uppere.g. after the laces are tensioned as shown in FIG. 21B. The shape ofthis last does not take into account additional materials that may berequired e.g. a large gusseted tongue, to allow the foot to fit into andout of the shoe and for the shoe to be used. Any additional materialrequirements are provided by separate cut and sewn pieces. FIG. 22represents the shape of the shoe showing the additional materialrequirements 401. To provide a seamless insert, such as PTFE or othersuitable material, which has a close fit to the shoe, the insert mustrepresent the shape of the shoe including these additional materialrequirements 401 in the gusseted tongue area 403. To account for theadditional material content required in a seamless insert, the presentinvention provides a unique modified last having a protruded gussetregion suitable for making seamless inserts of the present invention,the last shown in FIG. 23.

In an alternative embodiment of the shoe lasts of the present invention,it is possible to provide lasts with add-on, separable components toattach to a conventional last to temporarily provide the unique shapedlast of the present invention. For example, typical shoe lasts, such asshown in FIG. 21A, are used routinely in footwear manufacturing. It ishighly desirable to temporarily (or permanently) modify these typicallasts using shapes and fixtures that can be added to the typical lastfor the purpose of modifying the last for the specific use ofmanufacturing shoes with the seamless insert in the method of thisinvention. FIGS. 24 and 25 show the additional part which comprises theprotruded gusset region 405 which is used to modify the conventionallast 407. Using a variety of techniques including machining, printingand casting, shapes can be formed which represent this additional shape405 to be attached to the conventional last 407. These shaped componentscan then be subsequently be attached to together using any of a varietyof suitable fixing techniques including, but not limited to, magnets,adhesives, clamps, screws, bolt fixtures. These additional shape 405fixtures can then be readily removed when traditional shoe making isresumed. Alternatively, a multiple piece, separable last iscontemplated.

In an alternative embodiment of the invention, a unique sockconfiguration is described and shown. To provide textiles that are usedas part of the seamless insert construction, such as a PTFE or urethaneconstruction, the textiles must form a close fit onto the modified lastwith no wrinkles, folds or loosely attached materials. Referring toFIGS. 26 and 27, typical tube (no heel) socks 409 provide very poorfitting to the modified last 404 of the present invention, with severewrinkles 411 and loose material. Conventional socks containing a heelare also unsuitable due to a tendency to form wrinkles and folds in thetongue and heel areas due to excess material and over tensioning.Referring to FIG. 28, to provide a textile with a very close fit to themodified last, the present invention provides a unique knitted sock 413having a heel reinforcement 415, capable of close fitting to the shoelast (not visible in drawing) with substantially no wrinkles, folds orexcess material evident. In addition to an improved sock configurationwhich is close fitting to the modified shoe last, the sock design mayincorporate additional design features to minimize tension formed duringshoe manufacture and actual use, e.g. when the tongue is fully extended.Referring to FIG. 29, it is contemplated that such design features mayinclude changing the fiber type/content to create an area of higherstretch 417 or incorporating specific knit designs in the gusset area toallow ease of moving the tongue forward without forming wrinkles anddefects through increasing tension.

It a further object of the present invention to provide a last for abootie, shoe insert, or waterproof, breathable sock that contains (1) alaminate of a conformed or shaped ePTFE membrane and at least onetextile and (2) a second component attached to the bootie, shoe insert,or waterproof, breathable sock, such as with a seam. In exemplaryembodiments, the ePTFE membrane is seamless. The second component maybe, for instance, a textile, a laminate (e.g., a laminate including apolymer membrane), a textile laminate, a polymer membrane (e.g.polytetrafluoroethylene or expanded polytetrafluoroethylene), or asecond conformed or shaped ePTFE membrane different from the firstconformed or shaped ePTFE membrane (e.g., having a characteristic orproperty different from the first conformed or shaped ePTFE membrane) inthe bootie, shoe insert, or waterproof, breathable sock. The selectionof the second material is not particularly limited, and may be selecteddepending on the desired quality or property desired. It is to beappreciated that the additional material(s) may be used, for example, totailor the bootie, shoe insert, or waterproof, breathable sock toachieve desired properties and/or a desired appearance.

It is yet another object of the present invention to provide a last fora hybrid bootie, shoe insert, or sock where a portion of the bootie,shoe insert, or sock is removed and the partial bootie, shoe insert, orsock is attached to a second component. The second component may beattached to the partial bootie, shoe insert, or sock by at least oneseam. In one embodiment, the bootie, shoe insert, or waterproof,breathable sock may be cut or otherwise portioned and that portionedpiece of the bootie, shoe insert, or waterproof, breathable sock may beattached to the second component.

It is also an object of the present invention to provide a last for abootie, shoe insert, or waterproof, breathable sock that includes aconformed ePTFE membrane that contains at least one integrally joinedinterface, and optionally, at least one textile. In some embodiments, asecond component may be attached to the bootie, shoe insert, orwaterproof sock (or a portion thereof) by any conventional methods, suchas by a seam.

It is another object of the present invention to provide a last for abootie, shoe insert, or waterproof, breathable sock that contains alaminate of a seamless conformed or shaped ePTFE membrane and at leastone textile where a portion of the laminate is removed and the partiallaminate is affixed to at least one second component.

It is an advantage of the present invention that for embodimentsincorporating ePTFE membrane, the ePTFE membrane in the bootie, shoeinsert, and waterproof sock may be seamless.

It is another advantage of the present invention that shoes made withshoe inserts having a seamless, shaped ePTFE membrane have enhancedbreathability over shoes made with conventional shoe inserts made bysewing together pieces of laminate material and sealing by a bonding orwelding process.

It is yet another advantage of the present invention that the shoeinserts conform closely to the inside of the shoe, thereby reducing andeven eliminating air gaps between the insert and the shoe.

It is a further advantage of the present invention that the bootie isconformable over a range of shoe sizes and shapes.

It is also an advantage of the present invention that the sole portionof the shoe may have breathability.

It is yet another advantage of the present invention that a shoe inserthaving a seamless, shaped ePTFE membrane contains little or no wrinkles,which increases wear comfort for the user.

It is a feature of the present invention that the bootie conforms in athermal heating step to shrink to fit a conventional asymmetrical lastover a range of sizes.

It is yet another feature of the present invention that the bootie canbe stretched to fit a conventional asymmetrical last over a range ofsizes.

It is also a feature of the present invention that a polymeric overlaymay be positioned on a bootie, shoe insert, or waterproof, breathablesock to provide additional cushioning, stability, and/or support.

It is another feature of the present invention that the inclusion ofpolymeric overlays on the shoe insert permits the “overlayed” shoeinsert to be worn in an indoor or outdoor environment without being partof a shoe.

It is a further feature of the present invention that the textile usedto form the shoe insert may be a conventional sock, a knitted textiletube, or a woven textile tube.

It is yet another feature of the present invention that the reduction orelimination of air gaps between the insert and the shoe reduces waterpick up.

It is also a feature of the present invention that the conformed orshaped ePTFE membrane may be densified such that the conformed or shapedePTFE membrane has a density greater than or equal to about 2.0 g/cm³,which renders the bootie, shoe insert, or sock non-breathable butprovides the wearer protection from an aggressive environment.

It is another feature of the present invention that the seamlessbooties, shoe inserts, and socks are breathable over their entireties.

It is another feature of the present invention that the lack of seamtape on the shaped ePTFE membrane within the shoe insert reduces theweight of the insert compared to conventional inserts or booties madewith seam tape.

DEFINITIONS

The term “conformable ePTFE tape” as used herein is meant to describe anePTFE structure that is extendable or extensible in a first direction,which recovers in a second direction perpendicular to the firstdirection, and which is elongated to conform to the shape of a threedimensional object without fracturing, tearing, or otherwise breaking.

The term “extensibility” as used herein is meant to define thecapability of the ePTFE tape to elongate or stretch.

The term “ePTFE membrane” as used herein with respect the formation ofthe booties, shoe inserts and socks described herein, is meant todescribe a conformable ePTFE tape that has been stretched or expandedover a three dimensional object and which substantially maintains thethree dimensional shape of the object. It is to be understood that the“ePTFE membranes” described herein are porous and have a microstructureof nodes interconnected by fibrils.

As used herein, the terms “sock”, “bootie”, and “shoe insert” are meantto describe footwear articles that encase the foot of the wearer.

The term “conformed” as used herein is meant to describe footweararticles (e.g., sock, bootie, or shoe insert) comprising an ePTFEmembrane, or an ePTFE membrane, having substantially the shape of asymmetrical last or a portion thereof.

The term “shaped” as used herein is meant to describe footwear articles(e.g., sock, bootie, or shoe insert) comprising an ePTFE membrane, or anePTFE membrane, having substantially the shape of an asymmetrical lastor a portion thereof.

As used herein, the term “textile” is meant to denote any woven,nonwoven, felt, knit, stretch spunbond nonwoven, stretch needlepunchednon woven, stretch spunlace non-woven, or fleece and can be composed ofnatural and/or synthetic fiber materials and/or other fibers or flockingmaterials that has at least some elastic properties.

The term “elastic” as used herein is meant to denote that the materialhas stretch characteristics and can be tensioned; and, upon the releaseof tension, the material returns to its approximate original dimensions.

The term “highly elastic” or “high elasticity” as used herein is meantto describe materials that have stretch characteristics and can betensioned at least about 50% (or greater); and, upon the release oftension, the material returns to its approximate original dimensions.

The term “seam” or “seamed” as used herein is meant to include thejoining of two portions, regions, or materials. A seam may join similaror identical materials or two or more dissimilar materials (e.g.dissimilar textile pieces or a laminate to a shoe insert). The terms“seam” and “seamed” are not intended to be limited to stitching and/orsewing. “Seam” and “seamed” as used herein are meant to include anysuitable means of joining two portions regions, or materials, such as byadhesives, bonding, welding, laminating, and the like.

The term “integrally joined interface” is meant to describe the joiningor attachment of a conformed or shaped ePTFE membrane to itself (i.e.,the same conformed or shaped ePTFE membrane), such as when the conformedor shaped ePTFE membrane has been folded, cut, torn, slit, punctured, orotherwise damaged. The joining or attachment of the conformed or shapedePTFE membrane to itself may be accomplished by any suitable means ofattachment, such as, for example, sewing, stitching, gluing, stapling,patching, etc.

The phrase “waterproof sock” is meant to describe a seamless waterproofsock made in accordance with the methods described herein.

The phrase “hybrid shoe insert” as used herein is meant to describe ashoe insert that has included therein one or more region(s) that has adifferent function(s) or different material(s) from the shoe insert.

The phrase “hybrid bootie” as used herein is meant to describe a bootiethat has included therein one or more region(s) that has a differentfunction(s) or different material(s) from the bootie.

The phrase “hybrid sock” as used herein is meant to describe a sock thathas included therein one or more region(s) that has a differentfunction(s) or different material(s) from the sock.

The term “waterproof” as used herein is meant to define a bootie, shoeinsert, shoe, or sock that meets the Waterproof Centrifuge Testsdescribed herein.

The term “self-supporting shoe insert” as used herein is meant todescribe a shoe insert that maintains an upright, substantially verticalorientation with respect to a horizontal surface without any externalsupport.

The term “self-supporting bootie” as used herein is meant to describe abootie that maintains an upright, substantially vertical orientationwith respect to a horizontal surface without any external support.

The term “self-supporting sock” as used herein is meant to describe asock that maintains an upright, substantially vertical orientation withrespect to a horizontal surface without any external support.

The term “thickness variation” as used herein is meant to describe aratio of the difference in thickness of the ePTFE membrane at a firstposition compared to a second position.

The term “amorphously locked” as used herein is meant to define an ePTFEmembrane that has been heated above the crystalline melt temperature ofthe PTFE.

The term “on” as used herein is meant to denote that when an element is“on” another element, it can be directly on the other element orintervening elements may also be present.

The terms “adjacent” and “adjacent to” as used herein are meant todenote that when an element is “adjacent” to another element, theelement may be directly adjacent to the other element or interveningelements may be present.

The term “over” as used herein is meant to denote that when an elementis “over” another element, it can be directly over the other element orintervening elements may also be present.

The terms “additional component” or “second component” as used hereinare meant to describe any material, such as a textile, a laminate (e.g.including a polymer membrane), a textile laminate, a polymer membrane(e.g., polytetrafluoroethylene or expanded polytetrafluoroethylene), asecond conformed or shaped ePTFE membrane different from the firstconformed or shaped ePTFE membrane (e.g., having a characteristic orproperty different from the first shaped ePTFE membrane), that isattached by at least one seam to a bootie, shoe insert, or breathablesock described herein.

BRIEF DESCRIPTIONS OF FIGURES

The advantages of this invention will be apparent upon consideration ofthe following detailed disclosure of the invention, especially whentaken in conjunction with the accompanying drawings wherein:

FIG. 1 is a schematic illustration depicting a cross section of alaminate forming a 2-layer shoe insert in accordance with the presentinvention having one textile layer;

FIG. 2 is a schematic illustration depicting a cross section of alaminate forming a 3-layer shoe insert according to the presentinvention where two textile layers are utilized;

FIG. 3A is a schematic illustration of a symmetrical last according toat least one embodiment of the invention;

FIG. 3B is a schematic illustration of the top view of the symmetricallast of FIG. 3A showing an axis of symmetry;

FIG. 4A is a schematic illustration of a conventional asymmetrical last;

FIG. 4B is a schematic illustration of the top view of the asymmetricallast of FIG. 4A showing no axis of symmetry;

FIG. 5 is a schematic illustration of a three-dimensional scan of thecross-section of a shoe containing the shoe insert according to at leastone embodiment of the invention taken at a position 3 cm from the end ofthe toe area of the shoe;

FIG. 6 is a schematic illustration of a three dimensional scan of thecross-section of the shoe depicted in FIG. 5 with an artificial footinsert positioned therein;

FIG. 7 is a schematic illustration of a three-dimensional scan of thecross-section of a shoe containing a conventional shoe insert taken at aposition 3 cm from the end of the toe area of the shoe;

FIG. 8 is a schematic illustration of a three-dimensional scan of thecross-section of the conventional shoe depicted in FIG. 7 containingtherein an artificial foot insert;

FIG. 9 is a schematic illustration of a heel and toe reinforced shoeinsert;

FIG. 10 is a schematic illustration of a cross-section of a shoe insertwithin a shoe comprising an upper and a sole;

FIG. 11 is a schematic illustration of a hybrid shoe insert according toone exemplary embodiment of the present invention;

FIG. 12 is a scanning electron micrograph (SEM) of the cross-section ofthe right upper portion of the shoe of Example 5 taken at 300×magnification;

FIG. 13 is a scanning electron micrograph of the cross-section of toeportion of the shoe of Example 5 taken at 300× magnification;

FIG. 14 is a cross-sectional schematic illustration of a shoe inserthaving thereon polymeric overlays;

FIG. 15 is a cross-sectional schematic illustration of a partial shoeinsert attached to an insole board;

FIG. 16 is a cross-sectional schematic illustration of a hybrid shoeinsert;

FIG. 17 is a cross-sectional schematic illustration of a hybrid shoeinsert position in a woman's dress shoe;

FIG. 18 is a cross-sectional schematic illustration of a shoe inserthaving therein a tear in the ePTFE membrane that has been repaired bystitching the ePTFE membrane together;

FIG. 19 is a cross-sectional illustration of a hybrid shoe insert havingtherein a cut that has been repaired by gluing the ePTFE membrane;

FIG. 20 is a cross-sectional illustration of a shoe insert where adamaged section of the shoe insert has been repaired by placing a patchon the shoe insert.

FIG. 21A is a side perspective view of a prior art shoe last;

FIG. 21B is a side perspective view of a prior art shoe last with a shoeassembled around the last;

FIG. 22 is a side perspective view of an embodiment of the presentinvention;

FIG. 23 is a side perspective view of a unique last of the presentinvention;

FIG. 24 is a side perspective view of a 2 part last of the presentinvention;

FIG. 25 is an exploded side perspective view of the last shown in FIG.24;

FIG. 26 is a side perspective view of the last of FIG. 23 with aconventional sock covering the last;

FIG. 27 is an alternate side perspective view of the last of FIG. 23with a conventional sock covering the last;

FIG. 28 is a side perspective view of an embodiment of a sock of thepresent invention; and

FIG. 29 is a side perspective view of an alternative embodiment of asock of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to lasts for three dimensional waterproof,breathable, and conformable booties and shoe inserts formed from theconformable booties, as well as footwear articles incorporating the shoeinserts therein. The present invention also relates to lasts for threedimensional waterproof, breathable socks. In alternative exemplaryembodiments, the booties, shoe inserts, and waterproof, breathable socksinclude a seamless ePTFE membrane and optionally, at least one textile.The bootie is conformable over a range of sizes and shoe shapes (e.g.,right and left). For instance, the bootie may be shaped to fit numeroussizes and shapes (e.g., right and left) of shoe lasts, therebyeliminating the need to have multiple sizes of shoe inserts correlatingto particular shoe sizes. The bootie may shrink to fit, or,alternatively, be stretched to fit, a last having a desired size to forma shoe insert. The shoe insert reduces or eliminates the need for awaterproof seam tape, which is conventionally used to make shoe insertswaterproof. It is to be appreciated that the terms “shoe” and “boot” asused herein is meant to include men's, women's, and children's shoes(casual, dress, and running) and boots, respectively.

The conformable ePTFE tape used in forming the booties, shoe inserts,and waterproof socks described herein is capable of elongating orstretching in a first direction and recovering in a second directionthat is perpendicular to the first direction. The conformable ePTFE tapehas an extensibility in the first direction from about 1.5× to about140×. In some embodiments, the conformable ePTFE tape has anextensibility in the first direction greater than about 3×, greater thanabout 10×, greater than about 30×, greater than about 40×, greater thanabout 50×, greater than about 60×, greater than about 70×, greater thanabout 80×, greater than about 90×, greater than about 100×, greater thanabout 110×, greater than about 120×, greater than about 130×, greaterthan about 140×, or even greater. The extensibility of the conformableePTFE tape may range from about 3× to about 130×, from about 10× toabout 120×, or from about 50× to about 100×. The conformable ePTFE tapemay or may not be heated prior to elongation or stretching.Additionally, the conformable ePTFE tape may be elongated or stretchedover a three dimensional object to conform to the shape of a threedimensional object without fracturing, tearing, or otherwise breaking.

One suitable example of a conformable ePTFE tape for use herein is aconformable expanded polytetrafluoroethylene (ePTFE) tape, such as anePTFE tape made in accordance with the teachings of U.S. Pat. No.7,306,729 to Bacino, et al, and described in detail in the Examples setforth below. It is envisioned that other suitable conformablemicroporous ePTFE tapes having an extensibility of at least 1.5× in atleast one direction may be utilized in forming the booties, shoeinserts, and waterproof socks, and would be easily identifiable by thoseof skill in the art. The pores of the conformable ePTFE tape may besufficiently tight so as to provide waterproofness, yet sufficientlyopen to provide properties such as moisture vapor transmission and thepenetration by coatings of colorants and oleophobic or othercompositions. The conformable ePTFE tape may be deformed at roomtemperature, or upon the application of heat, into an ePTFE membranehaving a three-dimensional shape. It is to be understood that the ePTFEmembranes described herein are porous and are characterized by amicrostructure of nodes interconnected by fibrils.

Expanded polytetrafluoroethylene (ePTFE) is described herein as anexemplary embodiment, but it is to be appreciated that expanded PTFE,expanded modified PTFE, and expanded copolymers of PTFE are allconsidered to be within the purview of the invention, and are allconsidered to be within the meaning of ePTFE as used herein. Patentshave been filed on expandable blends of PTFE, expandable modified PTFE,and expanded copolymers of PTFE, such as U.S. Pat. No. 5,708,044 toBranca; U.S. Pat. No. 6,541,589 to Baillie; U.S. Pat. No. 7,531,611 toSabol et al.; U.S. patent application Ser. No. 11/906,877 to Ford; andU.S. patent application Ser. No. 12/410,050 to Xu et al.

In addition, the incorporation of filler materials in various formswithin the conformable ePTFE tape and/or ePTFE membranes is alsoconsidered to be within the purview of the invention. Non-limitingexamples of suitable filler materials include carbon black, aerogels,metals, semi-metals, ceramics, carbon/metal particulate blends,activated carbon, and the like. Filler materials may be incorporatedinto the ePTFE tape and/or ePTFE membrane by conventional methods, suchas those described in U.S. Pat. No. 4,995,296 to Mortimer, Jr.

To minimize membrane variability during the formation of the shoeinsert, a symmetrical foot last may be utilized. A schematicillustration of a symmetrical last 80 is depicted in FIGS. 3A and 3B.The last 80 may be formed of virtually any material, such as, forexample, a polymer (e.g., nylon) or a metal (e.g., aluminum materials).A silicon coating, or other suitable coating, may be applied to act as arelease liner. Unlike conventional lasts, the symmetrical last 80 has noleft or right features or designations. As shown in FIG. 3B, thesymmetrical last 80 is symmetrical along a centrally located axisrepresented by reference numeral 105. Thus, the portions 82 and 84 oneither side of the centrally located axis 105 are mirror images, orsubstantially mirror images of each other. It is to be appreciated thatthe symmetrical last 80 may be formed to have different shapes and/orsizes depending on the end use of the article. For example, a shoeinsert for a running shoe and a shoe insert for a casual shoe may bemade using different symmetrical lasts due to the different and specificneeds of the two shoe types. Additionally, the symmetrical design of thelast can be changed to allow for additional shoe construction features,such as, for example, additional tongue gusset materials, size, width,shoe types, etc, so long as the symmetry along a centrally located axisremains intact. The symmetrical last 80 can therefore be customized tomeet a variety of shapes and sizes to meet desired end uses.

Additionally, the symmetrical last 80 minimizes and even avoids materialstress peaks and subsequent membrane thinning and fracture during theformation of booties, socks, and shoe inserts that would result from atraditional asymmetrical foot-shaped last 85, such as is depicted inFIGS. 4A and 4B. Such a foot-shaped last is conventionally used in shoeconstruction processes and contains distinctive left and right featuresand/or left and right foot designations. A symmetrical shoe insert withno left or right bias, such as is shown in FIGS. 3A and 3B, produces asuitable precursor for the subsequent thermal conformation processestaught herein.

In an alternative embodiment of the present invention, it may bedesirable to provide a unique shoe last which has a unique configurationto improve the geometry, and correspondingly the resulting performanceand fit, of the resulting seamless PTFE shoe inserts, booties, socks orother footwear assemblies.

Turning to FIG. 1, a schematic, cross-sectional view of a waterproof,breathable laminate 10 having a seamless, conformed ePTFE layer 20, anadhesive layer 40, and a textile layer 30 can be seen. The terms“textile(s)” and “textile layer(s)” may be used interchangeably herein.In forming the laminate 10 of a 2-layer article, an adhesive 40 may beapplied to one side of a textile 30, and the textile/adhesive compositemay be positioned on a symmetrical last 80 with the adhesive side facingoutwardly, i.e., away from the last. It is to be noted that positioningthe textile on the symmetrical last 80 prior to applying the adhesive 40to the textile 30 is within the scope of the invention. Alternatively,the adhesive 40 may be positioned on a side of a conformable ePTFE tapeand the ePTFE tape positioned such that the adhesive 40 faces thetextile 30 on the symmetrical last 80.

The adhesive may be applied discontinuously or continuously, providedthat breathability through the laminate is maintained. For example, anadhesive may be applied in the form of discontinuous attachments, suchas by discrete dots or in a grid pattern, or in the form of an adhesiveweb to adhere the layers of the laminate together. Alternatively, abreathable adhesive may be applied in a continuous manner to form alayer of adhesive to adhere the layers of the laminate together. Theadhesive may be a layer of a thermo-activatable adhesive whereactivation of the adhesive can be affected by a heating device. Althoughthe use of adhesives is described herein with respect to joining (e.g.,laminating) the textile layer to the ePTFE tape, it is to be noted thatany suitable process may be used, such as stitching, sewing, gluing,ultrasonic bonding, radio frequency welding, flame bonding, heat sealinggravure lamination, fusion bonding, spray adhesive bonding, and thelike.

The textile used to form the booties, shoe inserts, and waterproof socksmay be any textile that is air permeable and breathable and that has atleast some elastic properties.

Elastic, as used herein, is meant to denote that the material hasstretch characteristics and can be tensioned; and, upon the release oftension, the material returns to its approximate original dimensions.When forming a sock, a textile having a high elasticity, or anelasticity of at least about 50%, at least about 75%, or at least about100% or greater. The term “highly elastic” as used herein is meant todescribe materials that have stretch characteristics and can betensioned at least about 50% (or greater); and, upon the release oftension, the material returns to its approximate original dimensions.

The textile may be comprised of materials such as, but not limited, tocotton, rayon, nylon, polyester, silk, lycra, spandex, elastane, andblends thereof. The weight of the material forming the textile is notparticularly limited except as required by the application. In someembodiments, the textile may impart sufficient abrasion resistance tothe laminate to provide adequate protection for the wearer of thearticle of footwear. Also, the textile may have a soft hand so that thewearer of the footwear article is comfortable.

In exemplary embodiments, the textile is a commercially available sockor a textile tube (e.g., knitted or woven textile tube). The sock ortextile tube may be formed of virtually any material or combination ofmaterials as long as the sock or textile tube is elastic or has at leastsome elastic characteristics. In addition, the sock may be tubular orgenerally tubular in shape, or may have a formed shape that is generallyin the shape of a foot. Such formed-shape socks may also have reinforcedareas, such as in the toe and/or heel regions. The inclusion of heel andtoe reinforcements results in the bootie and/or shoe insert having amore defined, foot-like shape. The bootie, shoe insert, and waterproof,breathable sock, may therefore have an upper portion, a heel portion, atoe portion, and a sole portion.

After the adhesive 30 is applied to either the textile 30 or to theconformable ePTFE tape, or both, the conformable ePTFE tape is stretchedover the symmetrical last 80. In exemplary embodiments, the symmetricallast 80 is attached to a rotatable arm and the last 80 is rotated tomove the last 80 through the conformable ePTFE tape, which stretches theconformable ePTFE tape over the last 80 and into a seamless, conformedePTFE membrane 20 having the general shape of the symmetrical last 80.The adhesive may be a continuous breathable adhesive or a discontinuousadhesive. The ePTFE tape may be held in a fixed orientation relative tothe last 80 prior to moving the symmetrical last 80 through theconformable ePTFE tape. In addition, the conformable ePTFE tape may bepre-heated prior to conforming the ePTFE tape over the last 80. It is tobe appreciated that other mechanisms may be used to mechanically “push”or otherwise move the symmetrical last 80 through the conformable ePTFEtape. Alternatively, the conformable ePTFE tape may be manuallystretched over the symmetrical last 80. At this stage in the process,the last 80 contains thereon the textile 30, adhesive 40, and theseamless, conformed ePTFE membrane 20 (i.e., a 2-layer article).

An abrasion resistant coating may be applied to the ePTFE membrane 20 toprotect the seamless, conformed ePTFE membrane 20 from wear and/ordamage. In a 2-layer article, an abrasion resistant coating may beapplied to the ePTFE membrane 20. In use, the 2-layer article may bepositioned such that the coating faces away from the foot (e.g.,positioned towards the shoe) or it may be positioned such that thecoating faces the foot of the wearer (i.e., positioned away from theshoe). An abrasion resistant coating may also or alternatively beapplied to the surface of the textile. The 2-layer article may bepositioned such that the coating faces either the shoe or the foot. Itis to be appreciated that other coatings (e.g., colorants, oleophobiccoatings, etc.) may be applied in addition to, or in place of, theabrasion resistant coating. The coating(s) may be applied to all or partof the surface(s) of the ePTFE membrane or to all or part of thesurface(s) of the textile.

In forming laminate 70 shown in FIG. 2, a second adhesive 60 is appliedto a second textile 50 and the second textile/adhesive composite isstretched over the symmetrical last 80 with the adhesive positioned onthe exposed surface of the ePTFE membrane. Thus, the symmetrical last 80has thereon the first textile 30, the first adhesive 40, a seamless,conformed ePTFE membrane 20, the second adhesive 60, and the secondtextile 50 (i.e., the 3-layer article). It is to be understood that thetextile layer 50 and adhesive layer 60 may be the same as, or differentfrom, the textile layer 30 and adhesive layer 40 of laminate 10.Additionally, it is to be appreciated that laminates 10, 70 may containany number of layers as long as the laminate meets the performanceproperties described herein.

In the 3-layer article an abrasion resistant coating may be applied toall or part of the surface of the first and/or second textile such thatthe coating faces the shoe (i.e., positioned away from the foot). Thecoating may also or alternatively be applied to all or part of thesurface of the first and/or second textile such that the abrasionresistant coating faces the foot (i.e., away from the shoe). Othercoatings may be applied in addition to, or in place of, the abrasionresistant coating.

The 2-layer article and the 3-layer article may form a bootie, shoeinsert, or a sock, depending, at least in part, on the textile used toform the article. For example, and as discussed below, a tubular shapedsock may be used to form a waterproof sock whereas a reinforced,foot-shaped sock may be used to form a bootie or shoe insert.

The 2-layer article and the symmetrical last 80 or the 3-layer articleand the symmetrical last 80, depending on the number of layers desiredin the bootie and/or shoe insert, are heated to a temperature from about50° C. to about 200° C. or from about 80° C. to about 160° C., andgenerally to about 160° C. (with or without vacuum) in a conforming stepto set the seamless, conformed ePTFE membrane 20 generally into theshape of the symmetrical last 80 and form a bootie. Accordingly, thebootie may be formed of a conformed ePTFE membrane and at least onetextile. In one embodiment, the ePTFE membrane is heated above thecrystalline melt point of PTFE, for example to a temperature betweenabout 340° C. and 375° C., to “amorphously lock” the ePTFE and preventfurther changes in shape and/or size of the bootie, reduce thestretchability of the bootie, and provide stability to the bootie.

The temperature in the conforming step is ultimately dependent upon theadhesive(s) utilized, and should not be so high as to degrade and/orrender useless any portion of the bootie, shoe insert, or waterproofsock described herein. Additionally, the conforming step adheres thetextile layer(s) to the ePTFE membrane 20, particularly when a vacuum isutilized. The heating may occur in a conventional oven, an aircirculating oven, or the like. It is to be appreciated that the 2-layerarticle or 3-layer article may be heated in the absence of thesymmetrical last 80, or partially heated while positioned on thesymmetrical last 80, with the remainder of the heating occurring in theabsence of the symmetrical last 80 to conform the seamless, conformedePTFE membrane 20, so long as the 2-layer article or 3-layer articledoes not lose the general shape of the symmetrical last 80.

Regardless of the number of ePTFE layers 20, textile layers 30, 50, oradhesive layers 40, 60 present in laminates 10, 70, the number ofadditional layers added, or the mechanism for bonding the materialstogether, the booties described herein will contain certain properties.For example, a bootie will have a breathability of at least 3 g/hr, atleast 5 g/h, at least 10 g/hr, at least 20 g/hr, or even at least 30g/hr, or greater. Additionally, the bootie is advantageously shapeableover a range of shoe sizes and shapes of lasts (e.g., left or right).Thus, booties according to the present invention can be manufactured asone size and be shrunk (or stretched) to fit a variety of shoe sizes,including men's, women's, and children's sizes.

After the bootie has been formed, it is removed from the symmetricallast 80 and loosely placed on a conventional asymmetrical last 85, whichhas left and right foot characteristics. The bootie and asymmetricallast 85 are then subjected to a shaping step where the bootie andasymmetrical last 85 are heated to a temperature from about 50° C. toabout 200° C. for about 5 min to about 30 min. The bootie and theasymmetrical last 85 may be heated in a conventional oven, an aircirculating oven, or the like. During this thermal dwell, the bootie“shrinks” and closely shapes to the shape and size of the conventionalasymmetrical last 85, forming a smooth and close fitting shoe insert tothat of the conventional last. In some embodiments, the ePTFE membrane“amorphously locked” by heating the ePTFE from about 340° C. and 375° C.to prevent further changes in shape and/or size of the shoe insert andreduce the stretchability of the shoe insert. The shoe insert on theconventional last 85 shows little-to-no wrinkles and has little, if any,excess material. After the heating is complete, the last 85 and shoeinsert are removed from the heat and allowed to cool, generally to atemperature less than about 50° C. The shoe insert may then be removedfrom the last. The shoe insert may also be permitted to cool prior toremoving the shoe insert from the asymmetrical last 85. The shoe insertis thus formed of a seamless, shaped ePTFE membrane with at least onetextile.

In an alternate embodiment, the bootie is formed to have a size somewhatsmaller than the size of the asymmetrical last 85, and is stretched tofit the asymmetrical last 85, with or without the application of heat,and optionally in a vacuum. It is to be appreciated that the bootie canbe stretched to fit lasts over a large range of shoe sizes, such as froma woman's sized shoe last to a men's sized shoe last.

The booties and shoe inserts may be self-supporting and maintain thethree-dimensional shape of the last even after the shoe insert isremoved from the last. By self-supporting, it is meant that the bootieor shoe insert (or waterproof, breathable sock described below)maintains an upright, substantially vertical orientation without anyexternal support. By substantially vertical orientation, it is meant todescribe a bootie or shoe insert that has an upright, verticalorientation or a nearly upright, vertical orientation. This isespecially the case when a heel and/or toe reinforced sock is used toform the bootie and/or shoe insert. A schematic depiction of a heel andtoe reinforced shoe insert is shown in FIG. 9. As shown, the shoe insert130 has a toe-reinforced portion 140 and a heel-reinforced portion 150.The collar 160 and the upper portion 155 of the shoe insert 130 are alsodepicted to achieve a general depiction of the sock as a whole. It is tobe noted that the lines drawn within the shoe insert 130 are toillustrate the general area that makes up the toe-reinforced portion140, the heel-reinforced portion, and the collar 160, and it not to beconstrued as a seam of any kind.

Additionally, the thickness of the conformed or shaped ePTFE membranevaries within the shoe insert, bootie, and waterproof sock (discussedbelow). Using the shoe insert 130 depicted in FIG. 9 merely as anillustrative example, the thickness of the shaped ePTFE membranemeasured at the heel portion 150 may be different than the thicknessmeasured at the toe portion 140 of the shoe insert 130. Similarly, thethickness of the shaped ePTFE membrane at the heel portion 150 may bedifferent than the thickness measured at the upper portion 155 of theshoe insert 130.

The ratio of the thickness variation of the conformed or shaped ePTFEmembrane within the shoe insert, bootie, or waterproof sock ranges from1.2:1 to 5:1, from 1.25:1 to 5:1, from 1.3:1 to 5:1, from 1.5:1 to 5:1,from 2:1 to 5:1, from 2:1 to 4:1, or from 2:1 to 3.1, depending upon thelocations selected within the shoe insert, bootie, or waterproof sock.In exemplary embodiments, the thickness variation of the conformed orshaped ePTFE membrane from a first location to a second location in theshoe insert, bootie, or waterproof sock is at least 1.2:1, at least1.25:1, at least 1.5:1, at least 2:1, at least 2.1:1, at least 2.5:1, atleast 3:1, at least 4:1, or at least 5:1 or even greater. The thicknessis measured from one side of the ePTFE membrane to the other side of theePTFE membrane. It is notable that the side portions and tongue portionof the shoe insert tend to have a thicker ePTFE membrane compared toother parts of the shoe insert, even though the side portions and tongueportion of the shoe insert receive the most stretching over thesymmetrical last.

The shoe insert may be used in the formation of footwear articles, suchas shoes and boots. A shoe or boot containing the shoe insert may beformed in any manner known to those of skill in the art. It is to benoted that all standard and/or conventional methods of making and/orassembling footwear articles as known by those of skill in the art maybe utilized, and are considered to be within the scope of the invention.For instance, molding pressing, gluing, stitching, fusion welding,fusion bonding, compression molding, upper bonding, ultrasonic welding,a well as any conventional or commercial tooling are considered to bewithin the purview of the invention.

In one embodiment, natural or synthetic upper materials may be stitchedtogether to form a shoe upper. Toe and heel protectors may then beattached to the shoe upper. A shoe insert may then be attached to theshoe upper by stitching and/or adhering the shoe insert to the collarportion of the upper of the shoe. The synthetic upper materials andstitched/adhered shoe insert may then be then repositioned onto aconventional asymmetric last where a rubber adhesive is placed on theheel, toe, and sole areas. Any suitable adhesive, such as a solventbased chloroprene rubber adhesive, may be used as the adhesive. It is tobe appreciated that a shoe may be made by placing the shoe insert into ashoe without any adhesive so that the shoe insert may be easily removedfrom the shoe if needed.

A protective layer, such as an ethylene vinyl acetate (EVA) layer, maybe adhered to an additional component (e.g., an insole board) with thepreviously applied rubber adhesive. The protective layer may also, oralternatively, be attached to the sole of the shoe insert. The shoeupper may then be lasted around the shoe insert and attached additionalcomponent to form a close fitting shoe insert with the synthetic uppermaterials. Thus, the shoe insert fits very closely to the contour of theouter portions of the shoe. Finally, a sole (synthetic material, rubber,or other natural material) may be attached to the insole of the shoeinsert using another adhesive, such as a solvent based polyurethaneadhesive, to complete the waterproof, breathable shoe construction.Shoes made with the shoe insert are highly breathable, and may have abreathability of at least 3 g/hr, or at least 5 g/hr or at least 10g/hr, or at least 15 g/hr, or at least 20 g/hr, or even at least 30g/hr, or greater. In one exemplary embodiment, the shoe or boot is madeentirely formed of breathable component, thus making the shoe or bootbreathable over its entirety. For example, a footwear article formed ofan upper portion, a shoe insert, and a sole portion, each of the upperportion, shoe insert, and sole may be breathable.

In another exemplary embodiment, the conformable ePTFE tape may be usedto form a waterproof, breathable sock. In particular, a 2-layer or3-layer article may be made as described in detail above with theexception that the symmetrical last is typically smaller in size thanthe size of the symmetrical last used to make the bootie and shoe insertdescribed above. The smaller symmetrical last allows the waterproof,breathable sock to maintain at least some elastic characteristics. Inexemplary embodiments, the sock(s) utilized to form the waterproof,breathable sock are tubular socks or knitted or woven textile tubes thatdo not contain toe and heel reinforcements and contain some fibers withhigh elasticity. Generally, the sock or textile tube used to form thewaterproof sock has a higher elasticity than the socks and textile tubesused to form the bootie and/or shoe insert, and may be “highly elastic”and have an elasticity of at least about 50%. It is to be appreciatedthat socks containing heel and/or toe reinforcements may be utilized toform a waterproof, breathable sock as long as the sock is highlyelastic.

In some embodiments, the waterproof breathable sock is typically formedon a symmetrical last of the present invention to provide conformedwaterproof, breathable socks. Additionally, in some embodiments, thewaterproof, breathable sock can undergo a shaping step in which the sockis shaped with the application of heat (e.g., in a conventional oven) ona conventional asymmetrical last to form a shaped waterproof, breathablesock. The waterproof, breathable socks typically have greater elasticitythan booties or shoe inserts due due, at least in part, to the elasticnature of the textile used (e.g. highly elastic sock or highly elastictextile tube). The waterproof, breathable socks have a breathability ofat least 3 g/hr, or at least 5 g/hr or at least 10 g/hr, or at least 15g/hr, at least 20 g/h, or even at least 30 g/hr, or greater.

In some embodiments, the bootie, shoe insert, or waterproof, orbreathable sock may have thereon a polymeric overlay. The overlay(s) maybe attached to the bootie, shoe insert, or waterproof, breathable sockby any suitable means such as, but not limited to, adhering, bonding, orstitching the overlay to the bootie or shoe insert. The application of apolymeric overlay (e.g. a thermoplastic or a thermoset material) mayprovide additional cushioning and/or support to the bootie, shoe insert,or waterproof, breathable sock. A shoe insert 190 with polymericoverlays 180, 185 is depicted schematically in FIG. 14. The polymericoverlays 180 provide both stability and support to the shoe insert 190.Polymeric overlay 185, which is positioned at the sole of the shoeinsert 190, also provides protection to the wearer's foot (indicated bydashed line 195) and a gripping surface for the shoe insert 190.Polymeric overlays 180, 185 may be joined to the shoe (or bootie orwaterproof, breathable sock) by any suitable attachment mechanisms, suchas, but not limited to a seam 200. The inclusion of polymeric overlaysmay permit the “overlayed” shoe insert to be worn in an indoor oroutdoor environment, without being part of a shoe. Similarly, thepresence of a polymeric overlay(s) on a bootie or waterproof, breathablesock provides additional support and/or protection to the bootie or sockand may permit the bootie or sock to be worn in an indoor or outdoorenvironment without any other laminates or textiles attached thereto orwithout the bootie being inserted into a shoe.

It is to be appreciated that in an alternative embodiment, laminates 10,70 may be pre-formed and subsequently and sequentially formed oversymmetrical last 80 and asymmetrical last 85 and heated as discussedabove to form the bootie and/or the shoe insert, and/or the waterproof,breathable sock.

In a separate embodiment, one or more laminate containing the seamless,shaped ePTFE membrane, such as, for example, laminate 10 or laminate 70,may be used to form a shoe insert. For example, appropriately sized andshaped laminate pieces may be joined at seamed portions to form a shoeinert. The seamed portions may then be rendered waterproof, such as bysuperimposing a waterproof sealant (e.g., a waterproof adhesive) or byapplying a waterproof tape through a bonding or welding process. As onenon-limiting example of forming a shoe insert, laminate 10 or 70 may becut into appropriately sized and shaped pieces and joined to form anupper portion and a sole portion of a shoe insert. The upper portion andthe sole portion may be joined in any conventional manner, such as bysewing, welding, or bonding the pieces together. The seams may then berendered waterproof such as by applying the waterproof adhesive or tapediscussed above. Prior to applying any waterproof adhesive or tape, theseamed, laminate shoe insert may be heated in a manner described abovein a shaping step to conform to an asymmetrical last 85.

In another embodiment, the conformable ePTFE tape may be stretched overa conventional asymmetric last and formed into a shoe insert in a singlestep. The shoe insert (either with or without the asymmetrical last) maybe heated to a temperature from about 50° C. to about 200° C. to reducethe ability of the ePTFE membrane to further stretch and/or to deform.The shoe insert may also be heated to a temperature from about 340° C.to about 375° C. to amorphously lock the conformed ePTFE membrane. Theshoe insert of this embodiment is formed of a seamless, conformed ePTFEmembrane that has a shape substantially similar to the asymmetric last.In addition, the shoe insert may have one or more polymeric overlaythereon.

In yet another embodiment, a shoe insert having a generally symmetricalshape and which does not contain a textile is formed in a one stepprocess. In this embodiment, the conformable ePTFE tape is stretchedover a symmetrical last to form the shoe insert. The shoe insert (eitherwith or without the symmetrical last) may be heated to a temperaturefrom about 50° C. to about 200° C. to reduce the ability of the ePTFEmembrane to further stretch and/or to deform. The shoe insert mayadditionally, or alternatively, be heated to a temperature from about340° C. to about 375° C. to amorphously lock the conformed ePTFEmembrane. The shoe insert of this embodiment is a seamless, conformedshoe insert having generally the shape of the symmetrical last. The shoeinsert may have one or more polymeric overlay thereon.

In a further embodiment, the conformable ePTFE tape may be stretchedover a conventional asymmetric last and made into a shoe insert in twosteps (e.g. a conforming and a shaping step). In this particularembodiment, the shoe insert does not contain any textile. For instance,the conformable ePTFE tape may be stretched over a symmetrical last andheated to a temperature (e.g., from about 50° C. to about 200° C.) in aconforming step to create a seamless, conformed ePTFE membrane having ashape that is generally the shape of the symmetrical last and form abootie. The bootie may then be positioned over an asymmetrical last andheated (e.g. 50° C. to about 200° C.) in a shaping step to shrink theePTFE membrane to fit the asymmetrical last and form a shoe insert. Theseamless, shaped ePTFE membrane may be “amorphously locked” by heatingthe shaped ePTFE membrane to a temperature between about 340° C. and375° C. to prevent further changes in shape and/or size of the shoeinsert and reduce the stretchability of the shoe insert. The seamless,shaped ePTFE membrane may have a coating thereon, such as, for example,to render the membrane hydrophobic, oleophobic, dimensionally stable,and/or abrasion resistant. Thus, a shoe insert may be made entirely of aseamless, shaped ePTFE membrane. In addition, the shoe insert may haveone or more polymeric overlay thereon.

Similarly, a waterproof, breathable sock made entirely of a seamless,conformed ePTFE membrane may be formed by not subjecting the seamlessconformed ePTFE membrane to the shaping step. Such a waterproof,breathable sock has a shape substantially similar to the symmetric last.It should be appreciated, however, that shaped waterproof, breathablesocks are within the scope of the present invention, as describedelsewhere herein.

In a further embodiment, the conformable ePTFE tape may be stretchedover a symmetric last and formed into a bootie in a single step. Thebootie (either with or without the symmetrical last) may be heated to atemperature from about 50° C. to about 200° C. to reduce the ability ofthe ePTFE membrane to further stretch and/or to deform or to atemperature from about 340° C. to about 375° C. to amorphously lock theconformed ePTFE membrane. The bootie is thus formed of a seamless,conformed ePTFE membrane that has a shape substantially similar to thesymmetric last. The bootie may have thereon one or more polymericoverlay.

In another embodiment, a bootie or shoe insert may be formed bypositioning a textile/adhesive composite on a symmetrical or anasymmetrical last as described in detail above. Next, a laminateincluding an ePTFE tape, a second adhesive, and a second textile may beformed. The bootie or shoe insert may be formed by stretching thelaminate over the textile/adhesive composite. Additional heating stepsas described herein may be conducted to finish forming the bootie orshoe insert.

The booties, shoe inserts, and waterproof, breathable socks describedabove have continuous, seamless layer(s) of ePTFE. In other words, eachconformed or shaped ePTFE membrane in the bootie, shoe insert, or shoeinsert is formed of a single conformed or shaped ePTFE membrane. Assuch, there are no seams in the conformed or shaped PTFE membrane withinthe booties, shoe inserts, and waterproof, breathable socks. Shoesformed with the shoe inserts are therefore more comfortable to wear,particularly when compared to conventional shoe inserts formed withseamed portions where laminate pieces are attached to each other. Asdiscussed herein, the shoe inserts having therein seamless shaped ePTFEmembranes do not form or contain, or only minimally form or contain,folds, wrinkles, or seams that would ultimately compromise thebreathability and/or fit of the shoe insert in the shoe.

Additionally, booties, shoe inserts, and waterproof, breathable sockshaving a seamless conformed or shaped ePTFE membrane described hereinare highly breathable over the entirety of the bootie, shoe insert, orwaterproof, breathable sock, which is at least partially due to thebreathable laminate forming the bootie, shoe insert, or waterproof,breathable sock and the lack of seams in the conformed or shaped ePTFEmembrane. For example, for a shoe insert having an upper portion, a heelportion, a toe potion, and a sole portion, each of these portions may bebreathable. Further, shoe inserts with a seamless, shaped ePTFE membranedemonstrate improved breathability over conventional shoe inserts thatare formed of multiple pieces of laminate sewn together, and oftensealed with a waterproof tape such as GORE-SEAM® tape (available from W.L. Gore and Associates, Inc.), which is not breathable. A crosssectional schematic view depicting the shoe insert 95 positioned withina shoe containing a shoe upper 90 and a sole 120 is depicted in FIG. 10.It is to be noted that a shoe insert with a seamless shaped ePTFEmembrane closely follow the contours of the shoe, leaving little to nospace or air gaps between the shoe insert and the shoe.

A second component may be attached to the bootie, shoe insert, orwaterproof, breathable sock to form a hybrid bootie, hybrid shoe insert,or hybrid sock. The second component may provide a different function orfeature and/or it may be formed of a different material from the bootie,shoe insert, or waterproof, breathable sock. The additional componentmay be, for instance, a textile, a laminate (e.g., a laminate includinga polymer membrane), a textile laminate, a polymer membrane, or a secondconformed or shaped ePTFE membrane different from the first conformed orshaped ePTFE membrane (e.g., having a characteristic or propertydifferent from the first conformed or shaped ePTFE membrane) in thebootie, shoe insert, or waterproof, breathable sock. The selection ofthe second component is not particularly limited, and may be chosendepending on the desired quality or property. It is to be appreciatedthat the second component(s) may be used, for example, to tailor thebootie, shoe insert, or waterproof, breathable sock to achieve desiredproperties and/or a desired appearance. The second component may beattached to the bootie, shoe insert, or waterproof, breathable sock byany conventional joining or attaching method. Non-limiting examples ofsuch methods include stitching, sewing, gluing, ultrasonic bonding,radio frequency welding, flame bonding, and heat sealing lamination,fusion bonding, spray adhesive bonding, and the like. Further, it is tobe noted that the terms “second component” and “second material” may beused interchangeably herein.

One example of a hybrid shoe insert 250 is depicted in FIG. 16. Thedepicted hybrid shoe insert 250 includes a shoe insert 220 attached to asecond component 230 (e.g., a textile, a laminate, a textile laminate, apolymer membrane, or a second shaped ePTFE membrane) by a seam 240,although, as discussed above, any method for joining the shoe insert 250to the second component 230 may be utilized. The hybrid shoe insert 250illustrated in FIG. 16 may be used in the formation of a boot, or in asituation where a portion located above the shoe insert 220 needs (or isdesired) to have a functionality or feature that is different from whatis provided by the shoe insert 220. It is to be appreciated that anynumber of portions or seams within the hybrid shoe insert as well as anynumber of positions for the seams, is considered to be within thepurview of the invention.

One embodiment containing various portions or regions within a shoeinsert is depicted in FIG. 11. The conformed/shaped ePTFE and textile(s)forming the shoe insert may be cut and portion(s) removed therefrom. Theportion(s) removed may then be replaced by one or more second component.In another embodiment, the portion that is removed may be attached to atleast one second component. The second materials may possess differingcharacteristics, such as, for example, different breathability and/ordifferent waterproofness and/or different aesthetic appearances. In oneor more embodiment, seams may be rendered waterproof by sealing theseams with a waterproof tape (e.g., GORE-SEAM® tape (available from W.L. Gore and Associates, Inc.). It is to be appreciated that the bootiecontaining one or more seams in FIG. 11 is merely illustrative, and oneor more seam may be utilized in the socks and booties described hereinin a similar manner.

In FIG. 11, the shoe insert contains two seams 175, which creates threeseparate “zones” or “regions” (illustrated as 1, 2, and 3, respectively)within the shoe insert. For example, zone 1 may contain the portionedshoe insert, and zones 2 and 3 may each contain a second component.Alternatively, zone 2 shown in FIG. 11 may contain the portioned shoeinsert and zones 1 and 3 may each contain a second material. It is to beappreciated that any combination of shoe insert portion(s) and secondcomponent(s) are within the purview of the invention. It is also to beunderstood that any number of zones (and seams) may be present in ahybrid bootie, hybrid shoe insert, or hybrid waterproof, breathablesock, and that such embodiments are considered to be within the purviewof the invention. Additionally, the joining mechanisms (e.g., stitchingor gluing) may be positioned in locations where the joining mechanism isnot likely to interfere with the comfort of the person donning thebootie, shoe insert, or sock.

In another embodiment, portions of the shoe inserts descried herein maybe used in shoe construction. For instance, the sole (bottom portion) ofa shoe insert may be removed and the partial shoe insert (e.g. upperportion of the shoe insert) may be attached to an additional component(e.g. insole board), such as is depicted schematically in FIG. 15.Specifically, FIG. 15 depicts a partial shoe insert 210 (with the soleremoved) adhered to an insole board 215 via an adhesive 225. It is to beappreciated that any suitable process for joining the partial shoeinsert to the additional component may be used, such as stitching,sewing, gluing, ultrasonic bonding, radio frequency welding, flamebonding, and heat sealing gravure lamination, fusion bonding, sprayadhesive bonding, injection molding, and the like. It is to beunderstood that any portion or part of the bootie or shoe insert may beremoved, including removal of one or more layers of the laminate such asby skiving, and that such partial booties and partial shoe inserts areconsidered to be within the scope of the invention.

A hybrid shoe insert may be utilized in both men's and women's shoes.One example of a hybrid shoe insert utilized within a woman's shoe isschematically depicted in FIG. 17. In this embodiment, the hybrid shoeinsert contains a shoe insert portion 305 and a second component portion310. Both the shoe insert portion 305 and the second component portion310 are located within a shoe 300, as depicted by the dashed lines. Inthis example, the component portion 310 may be formed of a textile, forexample, for ease comfort when wearing the shoe 300. Similar to the shoeinserts described above, hybrid shoe inserts fit very closely to thecontour of the outer portion 315 of the shoe 300.

It is to be appreciated that although seams are referenced herein withrespect to hybrid shoe inserts any of the booties, shoe inserts, orwaterproof, breathable socks described herein may contain at least oneseam as described above. Any number of seams, as well as any number ofregions formed by the seams, are considered within the scope of theinvention.

In some instances, the conformed or shaped ePTFE membrane may be cut,slit, torn, punctured, or otherwise damaged, either during themanufacturing of the bootie, shoe insert, or waterproof, breathable sockor after the bootie, shoe insert, or sock has been made. In a situationwhere the conformed or shaped ePTFE becomes discontinuous (such as wherethe conformed or shaped ePTFE membrane is damaged or torn), theconformed or shaped ePTFE membrane may be joined (e.g., repaired) byattaching the conformed or shaped ePTFE membrane to itself at anintegrally joined interface. In one exemplary embodiment shown in FIG.18, a shoe insert 300 containing a shaped ePTFE membrane having a cut ortear therein may be joined (e.g., stitched) together at an integrallyjoined interface 310. In another exemplary embodiment depicted in FIG.19, a tear may be present in the shaped ePTFE membrane in a hybrid shoeinsert 320 containing a shoe insert portion 220 and a second component230 joined at seam 240. The shaped ePTFE may be joined to itself at anintegrally joined interface 225 by an adhesive 235. In a furtherembodiment, the ePTFE may be folded at an integrally formed interfacefor aesthetic reasons, such as to form a pleat or tuck.

In a further embodiment, a tear or other damage in a conformed or shapedePTFE membrane may be repaired by utilizing a patch, such as is shown inFIG. 20. In FIG. 20, damage to the shaped ePTFE membrane in the shoeinsert 330 has been repaired by positioning a patch 340 over the damagedarea. The patch may be adhered, stitched, or otherwise affixed to theshoe insert 330. It is to be appreciated that a shoe inserts containinga damaged shaped ePTFE membrane are merely illustrative, and one or moreintegrally joined interface may be utilized in the booties and socksdescribed herein in a similar manner.

In yet another embodiment, an elastic or at least partially elastictubular textile may be utilized to form a sock by applying an adhesiveto the tubular textile and positioning the tubular textile/adhesivecomposite on a symmetrical last with the adhesive positioned outwardly,away from the symmetrical last. The symmetrical last may then be pushedthrough the conformable ePTFE tape to position the conformable ePTFEmembrane on the tubular textile. The tubular textile with the ePTFEmembrane thereon may be seamed at the toe portion to form a sock.

In a further embodiment, the ePTFE membrane may be densified by anyconventional method such that the ePTFE membrane has a density of 2.0g/cm³ or greater. Booties, shoe inserts, and socks may be formed withsuch densified ePTFE membranes; however, the booties, shoe inserts, andsocks made from the densified ePTFE membranes would not be breathable.The densified ePTFE membrane provides protection against aggressiveenvironments, such as, but not limited to, exposure to hazardouschemicals or biological threats.

Test Methods

It should be understood that although certain methods and equipment aredescribed below, any method or equipment determined suitable by one ofordinary skill in the art may be alternatively utilized.

Conformability Assessments

To assess the conformability of the shoe insert in the formed shoe, thesurface of the inner shoe can be felt by hand to determine any folds,wrinkles or seams that would ultimately compromise comfort fit. Inaddition, the shoes can be scanned using a scanning device to visuallydetermine the presence or absence of air gaps to indicate how closelythe shoe insert fits to the upper shoe materials.

Whole Boot Moisture Vapor Transmission Rate Test

The Whole Boot Moisture Vapor Transmission Rate for each sample wasdetermined in accordance with the Department of Defense Army Combat BootTemperate Weather Specifications. The specifications are as follows:

Whole Boot Breathability

The boot breathability test shall be designed to indicate the MoistureVapor Transmission Rate (MVTR) through the test sample by means of adifference in concentration of moisture vapor between the interior andthe exterior environment.

Apparatus

a. The external test environment control system shall be capable ofmaintaining 23 (±1° C. and 50%±2% relative humidity throughout the testduration.

b. The weight scale shall be capable of determining the weight of testsamples filled with water to an accuracy of (±0.01) gram.

c. The water holding bag shall be flexible so that it can be insertedinto the test sample and conform to the interior contours; it must bethin enough so that folds do not create air gaps; it must have muchhigher MVTR than the footwear product to be tested; and it must bewaterproof so that only moisture vapor contacts the interior of thefootwear product rather than liquid water.

d. The internal heater for the test sample shall be capable ofcontrolling the temperature of the liquid water uniformly in the testsample to 35 (±1)° C.

e. The sealing method around the collar of the test sample shall beimpervious to both liquid water and water vapor.

Procedure

a. Place sample in test environment and condition for at least 12 hours,

b. The heating device is inserted into the water holding bag and thecomplete assembly is then placed into the test sample opening and filledwith water to a height of 5 cm measured from inside sole.

c. Seal opening around the collar with plastic wrap around the top ofthe footwear and tape over using packaging tape.

d. Heat water in test sample to 35° C.

e. Weigh test sample and record as Wi.

f. Hold temperature in test sample after weighing for a minimum of 4hours.

g. After a minimum of 4 hours, reweigh test sample. Record weight as Wfand test duration as Td.

h. Calculate MVTR of the test sample in grams/hour from the equationbelow: MVTR=(Wi−Wf)/Td

Shoe and Shoe Insert Centrifuge Waterproofness Tests

-   -   (1) Waterproofness for each shoe sample was determined by use of        the Centrifuge test described in U.S. Pat. No. 5,329,807 to        Sugar, et al. assigned to W.L. Gore and Associates, Inc. and        incorporated by reference herein in its entirety. The centrifuge        tests were carried out for 30 minutes. The shoe sample was        considered to be waterproof if no leakage was seen after 30        minutes

(2) Waterproofness for the 2-layer bootie samples and shoe insertsamples (bootie after thermally conforming to a 265 sized running shoelast) was determined by a modified Centrifuge test described in U.S.Pat. No. 5,329,807 to Sugar, et al. assigned to W.L. Gore andAssociates, Inc. To ensure accurate waterproof testing of socks, 800 mlsof water was added to each sample which was then secured on a fixtureusing hose clamps around the rim of the upper heel area of the sock. Thecentrifuge tests were carried out for 60 minutes. The sample wasconsidered to be waterproof if no leakage was seen after 60 minutes,

Sock Moisture Vapor Transmission Rate Test

The Moisture Vapor Transmission Rate for each sock was determined inaccordance with Department of Defense Army Combat Boot Temperate WeatherSpecification with the exception that a sock was used as the testsample. The specifications were as follows:

The sock breathability test shall be designed to indicate the MoistureVapor Transmission Rate (MVTR) through the sock by means of a differencein concentration of moisture vapor between the interior of the sock andthe exterior environment of the sock.

Apparatus.

a. The external test environment control system shall be capable ofmaintaining 23 (±1° C. and 50%±2% relative humidity throughout the testduration.

b. The weight scale shall be capable of determining the weight of testsamples filled with water to an accuracy of (±0.01) gram.

c. The water holding bag shall be flexible so that it can be insertedinto the test sample and conform to the interior contours; it must bethin enough so that folds do not create air gaps; it must have muchhigher MVTR than the footwear product to be tested; and it must bewaterproof so that only moisture vapor contacts the interior of thefootwear product rather than liquid water.

d. The internal heater for the test sample shall be capable ofcontrolling the temperature of the liquid water uniformly in the testsample to 35 (±1) ° C.

e. The sealing method around the collar of the test sample shall beimpervious to both liquid water and water vapor.

Procedure.

a. Place sample in test environment and condition for at least 12 hours.

b. The heating device is inserted into the water holding bag and thecomplete assembly is then placed into the test sample opening and filledwith water to a height of 5 cm measured from inside sole.

c. Seal opening around the collar with plastic wrap around the top ofthe footwear and tape over using packaging tape.

d. Heat water in test sample to 35° C.

e. Weigh test sample and record as Wi.

f. Hold temperature in test sample after weighing for a minimum of 4hours.

g. After a minimum of 4 hours, reweigh test sample. Record weight as Wfand test duration as Td.

h. Calculate MVTR of the test sample in grams/hour from the equationbelow: MVTR=(Wi−Wf)/Td

As a further modification and to represent the sock moisture vaportransmission rate when the sock is worn in a shoe, the moisture vaportransmission rate tests were repeated with the socks placed in a largesize running shoe taking care to minimize air gaps. The same runningshoe was used in each test and was dried using a hot air drier betweentests. Throughout the tests, the total weight of the sock and shoe wasmeasured to determine water vapor transmission rates.

A running shoe was made with synthetic upper materials (part numberDMT20130502, commercially available from Dong Min Textile, 3173-24,Mungji-Dong, Gangseo-Ku, Busan, Korea). The synthetic upper materials ofthe shoe were stitched together to form the upper of the shoe. Toe andheel protectors were then attached to the upper of the shoe. A 6 ozcanvas toe puff (commercially available from Dae Kyung Tex Co. #C-135Gamjeon-dong Sasang-Gu, Busan, Korea) and a Rhenoflex 3105 heel counterhaving a thickness of 1.6 mm (commercially available from Rhenoflex,Giulinistrasse 2 67065 Ludwigshafen, Germany) were obtained and attachedto the upper of the shoe. No liner materials were added.

The upper materials were then repositioned onto a large sized runningshoe last and a solvent based chloroprene rubber adhesive was placed onthe heel and toe areas (8250 supplied by Henkel Technologies Korea,604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea) and sole (8700Hsupplied by Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong,Saha-Ku, Busan, Korea) area. A protective EVA layer (2.0 mm, hardness 55supplied by Dong Bo S.M. Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan,Korea) was adhered to a non woven insole board (1.4 mm supplied by HanYoung Industry Co., Ltd, #394-5 Samrak-dong Sang-Gu, Busan, Korea) usinga solvent based chloroprene rubber adhesive (8700H supplied by HenkelTechnologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea).The upper materials were then lasted around the attached insole board,as known in the art to form a close fitting liner with the uppermaterials. Finally, a rubber sole was attached to the insole board usinga solvent based polyurethane adhesive (6190S, part number ZY30204093)available from Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong,Saha-Ku, Busan, Korea to complete the shoe construction.

Sock Centrifuge Waterproofness Test

Waterproofness for each sock test sample was determined by use of theCentrifuge test described in U.S. Pat. No. 5,329,807 to Sugar, et al.assigned to W.L. Gore and Associates, Inc. To ensure accurate waterprooftesting of socks, 700 mls of water was added to each sock test samplewhich was then secured on a fixture using hose clamps around the rim ofthe upper heel area of the sock. The centrifuge tests were carried outfor 60 minutes. The sock test sample was considered to be waterproof ifno leakage was seen after 60 minutes.

Expanded PTFE Tape Characterization

The expanded PTFE tape utilized in the Examples set forth herein wastested according to the ASTM 638 Plastic Tensile Strength Test. Three(3) samples were taken from the PTFE tape in both longitudinal (machine)and transverse directions. Average values for the three samples werecalculated.

The longitudinal samples had a thickness of 0.28 mm, a mass per area of226 g/m², a bulk density of 0.80 g/cc, a maximum load of 8.68 kgf and anextensibility (strain at max load) of a strain at max load of 34%. Thetransverse samples had a thickness of 0.28 mm, a mass per area of 220g/m², a bulk density of 0.77 g/cc, a maximum load of 0.11 kgf and anextensibility (strain at max load) of 8422%.

EXAMPLES Example 1

A symmetrical cast aluminum foot last having a shape as depictedgenerally in FIG. 3 was fixed onto a clamp which can rotated through anangle of approximately 140° using a pneumatic cylinder. A polyurethaneadhesive web (UT8, 20 g/m² polyurethane non-woven hot melt adhesivecommercially available from Protechnic, 41 Avenue Montaigne, F-68700,Cernay, France) was applied to one side of a commercially available 30denier (33 dtex) 100% Polyamid black sock (Knie 30 Leicht deckendobtained from the Nur Die GmbH, Rheine, Germany) using a heat press setat 130° C. and effective pressure of 5 psi. The sock with thepolyurethane adhesive web thereon was positioned tightly over the last.The sock was applied to the last with the adhesive web exposed on theouter surface of the last. Care was taken when applying the sock to thelast to avoid wrinkles.

A fine powder of PTFE polymer (Daiken Industries, Ltd., Orangeburg,N.Y.) was blended with Isopar® K (Exxon Mobil Corp., Fairfax, Va.) inthe proportion of 0.196 g/g of fine powder. The lubricated powder wascompressed in a cylinder to form a pellet and placed into an oven set at70° C. for approximately 12 hours. Compressed and heated pellets wereram extruded to produce tapes approximately 15.2 cm wide by 0.73 mmthick. Three separate rolls of tape were produced and layered togetherbetween compression rolls to a thickness of 0.76 cm. The tape was thentransversely stretched to 56 cm (i.e., at a ratio of 3.7:1), restrained,and then dried in an oven set at 270° C. The dry tape was longitudinallyexpanded between banks of rolls over a heated plate set to a temperatureof 340° C. The speed ratio between the second bank of rolls and thefirst bank of rolls, and hence the expansion ratio, was 8:1.

A portion of the expanded PTFE tape having a length of approximately 1meter and a width of approximately 12.5 cm was fixed in a frame byplacing the edges of the PTFE tape between two securing metal plates.The tape was further secured by compressing the PTFE tape between theplates using 5 screw bolts positioned along the tape length. To ensurethat the width of the PTFE tape remained fixed, each tape edge and plateassembly was secured to the frame using locking nuts. The secured PTFEtape in the frame had a width of 9 cm.

The complete frame containing the PTFE tape and securing plates werethen placed under an IR heater set at 100% (full power) for 10 secondsduring which the tape reached a temperature of 40-50° C. The lockingnuts were then released and the edges of the tape were slowly, manuallymoved apart until the tape was expanded in the width direction to awidth of 27 cm. To prevent shrink back of the PTFE tape and to maintainthe 27 cm tape width, the frame edges were again secured using thelocking nuts. After the PTFE tape was expanded in the width directionand secured using the locking nuts, the tape was heated under the IRheater, which was set at 100% (full power) for 30 seconds, during whichthe tape reached a temperature of 70-80° C.

The frame containing the expanded PTFE tape was then quickly removedfrom under the heater and positioned above the symmetrical last. Thepneumatic cylinder was then activated to allow the symmetrical lasthaving thereon the sock and adhesive to rotate upwardly at an angle of90° to penetrate and deform the preheated PTFE tape around the last. Thefinal deformation of the tape to conform the tape to the general shapeof the last was completed by hand to ensure that the tape was deformedclosely to the shape of the last and to minimize wrinkles.

A second commercially available 30 denier (33 dtex) 100% Polyamid blacksock (Knie 30 Leicht deckend commercially available from Nur Die GmbH,Rheine, Germany) having thereon a polyurethane adhesive web (UT8, 20g/m² polyurethane non-woven hot melt adhesive commercially availablefrom Protechnic, 41 Avenue Montaigne, F-68700, Cernay, France) was thenplaced over the deformed PTFE tape with the polyurethane adhesivepositioned in direct contact with the surface of the deformed expandedPTFE tape. Care was taken to minimize wrinkling of the PTFE tape and thesock.

The resulting 3-layer article (i.e., sock/deformed, expanded PTFEtape/sock) was then secured at the collar of the last using anelastomeric retaining band to prevent further movement. The completeassembly containing the 3-layer article and the symmetrical aluminumlast was then placed in an oven set at 160° C. for a time of 45 min.During this thermal dwell time, the assembly reached an approximatetemperature of 130° C. The assembly was then removed and a siliconvacuum bag was quickly applied over the assembly. A vacuum was appliedat 20-25 inches Hg for 10 min to ensure good contact between the threeseparate layers and to allow for subsequent adhesive bonding between thesocks and the expanded PTFE tape. Cool, compressed air was then passedthrough the assembly for an additional 10-20 min while under vacuum tocool the assembly to approximately 50° C. The vacuum and compressed airwere removed from the assembly. Next, the silicon bag was removed. Theelastomeric retaining band was removed from the last. Finally, thecompleted 3-layer bootie was slowly and carefully removed from the last.

Example 2

A symmetrical nylon foot last having a shape as depicted generally inFIG. 3 was fixed onto a clamp which can be rotated through an angle ofapproximately 140° using a pneumatic cylinder. A polyurethane adhesiveweb (UT8, 20 g/m² polyurethane non-woven hot melt adhesive obtained fromProtechnic, 41 Avenue Montaigne, F-68700, Cernay, France) was applied toone side of a commercially available 60 den (66 dtex) 61% polyamide, 37%cotton, and 2% elastane black sock (Sockchen Naturelle 60 obtained fromthe Nur Die GmbH, Rheine, Germany) using a heat press set at 130° C. andan effective pressure of 5 psi. The sock with the polyurethane adhesiveweb thereon was positioned tightly over the last. The sock was appliedto the last with the adhesive web exposed on the outer surface of thelast. Care was taken when applying the sock to the last to avoidwrinkles.

A portion of the expanded PTFE tape produced in Example 1 having alength of approximately 1 meter and a width of approximately 7.4 cm wasobtained and fixed in a frame by placing the edges of the PTFE tapebetween six toggle clamps positioned along the tape edges andcompressing between two rubber seals. To ensure that the width remainedfixed, each tape edge and clamp assembly was fixed to the frame usinglocking nuts. The secured tape in the frame had a width of 6.9 cm.

The tape fixed in the frame was then heated using an industrial airheater for approximately 20 seconds, during which the PTFE tape reacheda temperature of 40-50° C. The locking nuts were then released and theedges of the tape were slowly, manually moved apart until the tape wasexpanded in the width direction to a width of 37.1 cm. To prevent shrinkback of the PTFE tape and to maintain the tape width, the frame edgeswere again secured using the locking nuts. After the PTFE tape wasexpanded in the width direction and secured using the locking nuts, thetape was then heated using the industrial air heater, during which thetape reached a temperature of approximately 70° C.

The frame containing the expanded PTFE tape was removed from the heatand positioned above the symmetrical last. The pneumatic cylinder wasthen activated to allow the symmetrical last having thereon the sock andadhesive to rotate in an upward direction at an angle of 90° topenetrate and deform the preheated PTFE tape around the last. The finaldeformation of the tape to conform the tape to the general shape of thelast was completed by hand to ensure that the tape deformed closely tothe shape of the last and to minimize wrinkles.

The 2-layer article (i.e., sock/deformed expanded PTFE tape) was thensecured at the collar of the last using an elastomeric retaining band toprevent further movement. The complete assembly containing the 2-layerarticle and nylon last was then placed in an oven set at 140° C. for atime of 30 min. During this dwell time, the assembly reached anapproximate temperature of 120° C. The assembly was then removed and avacuum bag was quickly applied over the assembly. A vacuum was appliedat 27 inches Hg until the assembly had cooled to approximately 50° C. toensure good contact between the two layers (i.e., sock and polyurethaneadhesive) and to allow for subsequent adhesive bonding between the sockand the expanded PTFE tape layer. The vacuum was then removed from theassembly. Next, the vacuum bag and the elastomeric retaining band wereremoved from the last. The completed 2-layer bootie was slowly andcarefully removed from the last.

The 2-layer bootie was then tested for water vapor permeability(breathability) using the Whole Boot Moisture Vapor Transmission Ratetest method outlined above with the expanded PTFE membrane layerpositioned on the exterior part of the test sample. The average watervapor permeability was determined to be 27.3 g/hr.

In addition, the 2-layer bootie was tested for waterproofness accordingto the Modified Centrifuge Test for waterproofness described above. Theshoe insert met the waterproofness standard, showing no water leaksafter 60 min.

Example 3

A 2-layer bootie was produced in the same manner as Example 2. A 2-layershoe insert was then thermally shaped by loosely placing the bootie ontoa conventional men's 265 running shoe last with the expanded PTFEmembrane layer exposed on the upper surface and heating the precursor inan air circulating oven at 140° C. for 30 min. During this thermaldwell, the shoe insert closely conformed to the shape and size of theconventional, asymmetrical last, thereby forming a smooth and closefitting shoe insert to the last. The last was removed from the oven andallowed to cool to less than 50° C., after which the two-layer shoeinsert was removed from the conventional, asymmetric last.

The three-dimensional shoe insert was then tested for water vaporpermeability (breathability) using the Whole Boot Moisture VaporTransmission Rate test method outlined above with the expanded PTFEmembrane layer exposed on the upper surface. The average water vaporpermeability was determined at 31.8 g/hr.

The three-dimensional shoe insert was also tested for waterproofnessaccording to the Modified Centrifuge Test for Waterproofness describedabove. The 2-layer bootie met the waterproofness standard, showing nowater leaks after 60 min.

Example 4

A waterproof running shoe was made with synthetic upper materialssuitable for a running shoe (part number DMT20130502 commerciallyavailable from Dong Min Textile, 3173-24, Mungji-Dong, Gangseo-Ku,Busan, Korea,). The synthetic upper materials of the shoe were stitchedtogether to form the upper of the shoe. Toe and heel protectors werethen attached to the upper of the shoe. A 6 oz canvas toe puff(commercially available from Dae Kyung Tex Co. #C-135 Gamjeon-dongSasang-Gu, Busan, Korea) and a Rhenoflex 3105 heel counter having athickness of 1.6 mm (commercially available from Rhenoflex,Giulinistrasse 2 67065 Ludwigshafen, Germany) were obtained and attachedto the upper of the shoe.

A 3-layer bootie was produced in the same manner as Example 1. A 3-layerbootie was thermally shaped by loosely placing the bootie onto aconventional men's 280 size running shoe asymmetrical last and heatingthe bootie and last in an air circulating oven at 140° C. for 30 min.During this thermal dwell, the bootie closely conformed to the shape andsize of the conventional, asymmetrical last, thereby forming a smoothand close fitting shoe insert to the last. The last was then removedfrom the oven and allowed to cool to less than 50° C., after which theshoe insert was removed from the conventional, asymmetric last.

During shoe production, the shaped shoe insert was again placed on the280 size running shoe last to form a smooth and close fit around thelast with no seams, noticeable wrinkles, or excess material. The shoeinsert was then cut and trimmed around the heel collar area to ensurethe shoe insert pattern was correctly sized.

The shoe insert was removed from the last and attached to the syntheticupper materials by stitching the shoe insert to the collar portion ofthe upper of the shoe. The synthetic upper materials and stitched shoeinsert were then repositioned onto the 280 size running shoe last and asolvent based chloroprene rubber adhesive was placed on the heel and toeareas (part number 8250 commercially available from Henkel TechnologiesKorea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea) and sole area(8700H supplied by Henkel Technologies Korea, 604-030, 472Shinpyung-Dong, Saha-Ku, Busan, Korea).

A protective ethylene vinyl acetate (EVA) layer (2.0 mm, hardness 55commercially available from Dong Bo S.M. Co., Ltd #520-36 Gouebob-dongSang-Gu, Busan, Korea) was adhered to a non-woven insole board (1.4 mmsupplied by Han Young Industry Co., Ltd, #394-5 Samrak-dong Sang-Gu,Busan, Korea) using the solvent based chloroprene rubber adhesive (8700Hcommercially available from Henkel Technologies Korea, 604-030, 472Shinpyung-Dong, Saha-Ku, Busan, Korea). The EVA protective layer wasthen attached to the sole of the shoe insert. The synthetic uppermaterials were then lasted around the shoe insert and attached insoleboard to form a close fitting shoe insert with the synthetic uppermaterials. Finally, a rubber sole was attached to the insole of the shoeinsert using a solvent based polyurethane adhesive (6190S, part numberZY30204093, commercially available from Henkel Technologies Korea,604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea) to complete the shoeconstruction.

Selected shoes were then tested for water vapor permeability(breathability) using the Whole Boot Moisture Vapor Transmission Ratetest method outlined above in the whole boot moisture vapor transmissionrate test. The average water vapor permeability was determined at 11.9g/hr.

The selected shoes were then tested for waterproofness according to theCentrifuge Test for Waterproofness described above. The selected shoesmet the waterproofness standard, showing no water leaks after 30 min.

Basic hand assessment of the surface characteristics of the inner shoeto assess the degree of fit of the shoe insert shows that no folds,wrinkles, or seams were present to compromise the comfort fitcharacteristics of the shoes.

Comparative Example 1

A waterproof shoe was made with synthetic upper materials suitable for arunning shoe (commercially available from Dong Min Textile, 3173-24,Mungji-Dong, Gangseo-Ku, Busan, Korea, part number DMT20130502). Thesynthetic upper materials were stitched together to form the upper ofthe waterproof shoe. A toe protector and heel protector were thenattached to the upper. A 6 oz canvas toe puff (supplied by Dae Kyung TexCo. #C-135 Gamjeon-dong Sasang-Gu, Busan, Korea) and a Rhenoflex 3105heel counter having a thickness of 1.6 mm (commercially available fromRhenoflex, Giulinistrasse 2 67065 Ludwigshafen, Germany) were obtainedand attached to the upper of the shoe.

A shoe insert made of a laminate of expanded polytetrafluoroethylene anda textile (part number VISI001001B, commercially available from W.L.Gore and Associates Inc., Elkton, Md.) was formed. The laminate was cutand stitched together to form a shoe insert of the correct size andshape of a 280 size running shoe last. GORE-SEAM® tape (commerciallyavailable from W.L. Gore and Associates Inc., Elkton, Md.) was thenapplied to the stitched seams of the shoe insert to form a waterproofseam. The shoe insert was then positioned on the 280 size running shoelast which formed a reasonable fit around the last, although wrinklesand excess material were noted.

The shoe insert was then removed from the last and attached to thesynthetic upper materials of the running shoe by stitching the shoeinsert to the collar portion of the upper. The synthetic upper materialsand stitched shoe insert were then repositioned onto the 280 sizerunning shoe last and a solvent based chloroprene rubber adhesive wasplaced on the heel and toe areas (8250 supplied by Henkel TechnologiesKorea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea) and sole area(8700H supplied by Henkel Technologies Korea, 604-030, 472Shinpyung-Dong, Saha-Ku, Busan, Korea). A protective EVA layer (2.0 mm,hardness 55 supplied by Dong Bo S.M. Co., Ltd #520-36 Gouebob-dongSang-Gu, Busan, Korea) was adhered to the non woven insole board (1.4 mmsupplied by Han Young Industry Co., Ltd, #394-5 Samrak-dong Sang-Gu,Busan, Korea) using a solvent based chloroprene rubber adhesive (8700Hsupplied by Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong,Saha-Ku, Busan, Korea) and the EVA protective layer was then attached tothe sole of the shoe insert. The upper materials were then lasted aroundthe shoe insert and attached insole board to form a close fitting shoeinsert with the upper materials. Finally, a rubber sole was attached tothe insole of the liner using a solvent based polyurethane adhesive(6190S, part number ZY30204093, commercially available from HenkelTechnologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea)to complete the shoe construction.

Selected shoes were then tested for water vapor permeability(breathability) using the Whole Boot Water Vapor Permeability testmethod outlined above in the whole boot moisture vapor transmission ratetest. The average water vapor permeability was determined at 8.8 g/hr.

The selected shoes were then tested for waterproofness utilizing theCentrifuge Test for Waterproofness described above showing no waterleaks after 30 min. The selected footwear met the waterproofnessstandard.

Basic hand assessment of the surface characteristics of the inner shoeto assess the degree of the fit of the shoe insert showed thatsignificant folds, wrinkles, and seams were present, especially in thetoe areas which would be expected to compromise comfort fitcharacteristics of the shoes.

Example 5

A waterproof running shoe was made with synthetic upper materialssuitable for a running shoe (part number DMT20130502, commerciallyavailable from Dong Min Textile, 3173-24, Mungji-Dong, Gangseo-Ku,Busan, Korea), The upper materials were stitched together to form theupper of the waterproof footwear. A 6 oz canvas toe puff (supplied byDae Kyung Tex Co. #C-135 Gamjeon-dong Sasang-Gu, Busan, Korea) and aRhenoflex 3105 heel counter having a 1.6 mm thickness (commerciallyavailable from Rhenoflex, Giulinistrasse 2 67065 Ludwigshafen, Germany)were attached to the upper of the shoe.

A 3-layer bootie was produced in the same manner as Example 1. The3-layer bootie was then thermally formed by loosely placing the bootieonto a conventional ladies 230 size running shoe asymmetrical last andheating the bootie and last in an air circulating oven at 140° C. for 30min. During this thermal dwell, the bootie closely formed to the shapeand size of the conventional, asymmetrical last, thereby forming asmooth and close fitting shoe insert to the last. The last was removedfrom the oven and allowed to cool to less than 50° C., after which theshoe insert was removed from the conventional, asymmetric last.

During shoe production, the shaped shoe insert was again placed on the230 size running shoe last to form a smooth and close fit around thelast with no seams, noticeable wrinkles, or excess material. The shoeinsert was then cut and trimmed around the heel collar area to ensurethe shoe insert pattern was correctly sized. The shoe insert was removedfrom the last and attached to the synthetic upper materials by stitchingthe shoe insert to the collar portion of the upper materials.

The upper materials and stitched shoe insert were then repositioned ontothe 230 size shoe last and a solvent based chloroprene rubber adhesivewas placed on the heel and toe areas (8250 supplied by HenkelTechnologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea)and sole area (8700H supplied by Henkel Technologies Korea, 604-030, 472Shinpyung-Dong, Saha-Ku, Busan, Korea). A protective EVA layer (2.0 mm,hardness 55 supplied by Dong Bo S.M. Co., Ltd #520-36 Gouebob-dongSang-Gu, Busan, Korea) was adhered to the non woven insole board (1.4mm, supplied by Han Young Industry Co., Ltd, #394-5 Samrak-dong Sang-Gu,Busan, Korea) using a solvent based chloroprene rubber adhesive (8700Hsupplied by Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong,Saha-Ku, Busan, Korea). The EVA protective layer was then attached tothe sole of the shoe insert. The upper materials were then lasted aroundthe shoe insert and attached insole board to form a close fitting shoeinsert with the upper materials. Finally, a rubber sole was attached tothe insole of the shoe insert using a solvent based polyurethaneadhesive (6190S, part number ZY30204093, commercially available fromHenkel Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan,Korea to complete the shoe construction.

Selected shoes were then tested for water vapor permeability(breathability) using the Whole Boot Water Vapor Permeability testmethod outlined above in the whole boot moisture vapor transmission ratetest. The average water vapor permeability was determined to be 11.0g/hr.

The selected shoes were then tested for waterproofness according to theCentrifuge Test for Waterproofness described above. The selectedfootwear met the waterproofness standard, showing no water leaks after30 min.

Basic hand assessment of the surface characteristics of the inner shoeto assess the degree of the fit of the shoe insert shows that no folds,wrinkles, or seams were present to compromise comfort fitcharacteristics of the shoes.

Three thickness measurements of the ePTFE membrane from the right sideupper portion of the shoe and of the ePTFE membrane from the toe portionwere measured and recorded. Average measurements were as follows: rightside upper portion=44.87 microns and toe portion=23.27 microns. Thethickness ratio was determined to be approximately 2:1. SEMs taken at300× magnification of the right side upper portion and toe portion areshown in FIGS. 12 and 13, respectively. The ePTFE membrane is identifiedas reference numeral 170.

Comparative Example 2

A waterproof running shoe was made with synthetic upper materialssuitable for a running shoe (part number DMT20130502, commerciallyavailable from Dong Min Textile, 3173-24, Mungji-Dong, Gangseo-Ku,Busan, Korea). The synthetic upper materials were stitched together toform the upper of the waterproof shoe. A 6 oz canvas toe puff (suppliedby Dae Kyung Tex Co. #C-135 Gamjeon-dong Sasang-Gu, Busan, Korea) and aRhenoflex 3105 heel counter having a thickness of 1.6 mm (supplied byRhenoflex, Giulinistrasse 2 67065 Ludwigshafen, Germany) were attachedto the upper of the shoe.

A shoe insert made of a laminate of expanded polytetrafluoroethylene anda textile (part number VISI001001B, commercially available from W.L.Gore and Associates, Inc., Elkton, Md.) was formed. The laminate was cutand stitched together to form a shoe insert having the size and shape ofthe 230 running shoe last. GORE-SEAM® tape (available from W.L. Gore andAssociates Inc., Elkton, Md.) was then applied to the stitched seams toform a waterproof seam over the stitched seams of the shoe insert. Theshoe insert was then placed on the 230 size shoe last which formed areasonable fit around the last, although wrinkles and excess materialwere noted.

The shoe insert was then removed from the last and attached to thesynthetic upper materials of the running shoe by stitching the liner tothe collar portion of the upper. The synthetic upper materials andstitched liner were then repositioned onto the 230 size shoe last and asolvent based chloroprene rubber adhesive was placed on the heel and toeareas (8250 supplied by Henkel Technologies Korea, 604-030, 472Shinpyung-Dong, Saha-Ku, Busan, Korea) and sole area (8700H supplied byHenkel Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan,Korea).

A protective EVA layer (2.0 mm, hardness 55 supplied by Dong Bo S.M.Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan, Korea) was adhered to thenon woven insole board (1.4 mm supplied by Han Young Industry Co., Ltd,#394-5 Samrak-dong Sang-Gu, Busan, Korea) using the solvent basedchloroprene rubber adhesive (8700H supplied by Henkel TechnologiesKorea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea). The EVAprotective layer was then attached to the sole of the shoe insert. Theupper materials were then lasted around the liner and attached insoleboard to form a close fitting shoe insert with the upper materials.Finally, a rubber sole was attached to the insole of the shoe insertusing a solvent based polyurethane adhesive (6190S, part numberZY30204093, commercially available from Henkel Technologies Korea,604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea) to complete the shoeconstruction.

Selected shoes were then tested for water vapor permeability(breathability) using the Whole Boot Water Vapor Permeability testmethod outlined above in the whole boot moisture vapor transmission ratetest. The average water vapor permeability was determined to be 6.4g/hr.

The selected shoes were then tested for waterproofness according to theCentrifuge Test for Waterproofness described above. The selectedfootwear met the waterproofness standard, showing no water leaks after30 min.

Basic hand assessment of the surface characteristics of the inner shoeto assess the degree of shoe insert fit shows that significant folds,wrinkles, and seams were present, especially in the toe areas that wouldbe expected to compromise comfort fit characteristics of the shoes.

Example 6

A waterproof casual shoe was made with natural split suede leather uppermaterials suitable for a casual shoe (part number JS120130501,commercially available from J. S. IND Co., Ltd. #1086-9, Janglim-Dong,Saha-Ku, Busan, Korea). The suede leather upper materials were stitchedtogether to form the upper of the waterproof shoe. A 0.6 mm toe puff(part number TFL060, commercially available from Han Young Industry Co.,Ltd, #394-5 Samrak-dong Sasang-Gu, Busan, Korea) and a 1.7 mm heelcounter leather board (supplied by Young Poly Chemical Co. Ltd. #907-7Manduck 3-dong Buk-Gu, Busan, Korea) were attached to the upper of theshoe.

A 3-layer bootie was produced in the same manner as Example 1. The3-layer bootie was then thermally formed by loosely placing the bootieonto a conventional men's 280 size casual shoe asymmetrical last andheating the bootie and last in an air circulating oven at 140° C. for 30min. During this thermal dwell, the bootie closely formed to the shapeand size of the conventional, asymmetrical last, thereby forming asmooth and close fitting shoe insert to the last. The last was removedfrom the oven and allowed to cool to less than 50° C., after which theshoe insert was removed from the conventional, asymmetric last.

During shoe production, the shaped shoe insert was again placed on themen's 280 size casual shoe last to form a smooth and close fit aroundthe last with no seams, noticeable wrinkles, or excess material. Theshoe insert was then cut and trimmed around the heel collar area toensure the shoe insert pattern was correctly sized. The shoe insert wasthen removed from the last and attached to the leather upper materialsof the casual shoe by stitching the shoe insert to the collar portion ofthe upper.

The suede leather upper materials and stitched liner were thenrepositioned onto the 280 size casual shoe last and a solvent basedchloroprene rubber adhesive was placed on the heel and toe areas (8250supplied by Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong,Saha-Ku, Busan, Korea) and sole areas (8700H supplied by HenkelTechnologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea).A protective EVA layer (2.0 mm, hardness 55, supplied by Dong Bo S.M.Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan, Korea) was adhered to theinsole board (A TEX 6331+Blue Tex commercially available from Dong BoS.M. Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan, Korea) using asolvent based chloroprene rubber adhesive (8700H supplied by HenkelTechnologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea).The EVA protective layer was then attached to the sole of the shoeinsert. The upper materials were then lasted around the liner andattached insole board. Finally, a rubber sole was attached to the insoleof the shoe insert using a solvent based polyurethane adhesive (6190S,part number ZY30204093, commercially available from Henkel TechnologiesKorea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea) to completethe shoe construction.

Selected shoes were then tested for water vapor permeability(breathability) using the Whole Boot Water Vapor Permeability testmethod outlined above in the whole boot moisture vapor transmission ratetest. The average water vapor permeability was determined to be 6.8g/hr.

The selected shoes were then tested for waterproofness according to theCentrifuge Test for Waterproofness described above. The selectedfootwear met the waterproofness standard, showing no water leaks after30 min.

Basic hand assessment of the surface characteristics of the inner shoeto assess the degree of fit of the shoe insert revealed that no folds,wrinkles or seams were present to compromise comfort fit characteristicsof the shoes. Utilizing 3D scanning equipment, images of the shoe crosssection at various positions along the shoe length were captured. FIG. 5represents a typical cross-sectional image at a position 3 cm from theend of the shoe toe area. The 3-layer shoe insert 95 showed a very closefit to the upper leather materials 90 with no evidence of folds, seams,and minimal air spaces.

In order to better illustrate the fit of the shoe insert in the shoeduring use, additional 3D scans were taken with an artificial footinsert of the appropriate size. A schematic illustration of such a scanof a cross-section of a shoe with an artificial foot positioned thereinis depicted in FIG. 6. As shown in FIG. 6, there is minimal contactbetween the shoe insert 95 and the foot insert 100. Such minimal contactindicated excellent comfort and excellent fit for the wearer of theshoe.

Comparative Example 3

A waterproof casual shoe was made with natural split suede leather uppermaterials suitable for a casual shoe (part number JS120130501commercially available from J. S. IND Co., Ltd. #1086-9, Janglim-Dong,Saha-Ku, Busan, Korea). The upper materials were stitched together toform the upper of the waterproof casual shoe. A 0.6 mm toe puff (partnumber TFL060, commercially available from Han Young Industry Co., Ltd,#394-5 Samrak-dong Sasang-Gu, Busan, Korea) and a 1.7 mm leather boardheel counter (supplied by Young Poly Chemical Co. Ltd. #907-7 Manduck3-dong Buk-Gu, Busan, Korea) were attached to the upper of the shoe. Ashoe insert were made of a laminate of expanded polytetrafluoroethyleneand a textile (part number VISI001001B, commercially available from W.L.Gore and Associates Inc., Elkton, Md.). The laminate was cut andstitched together to form a shoe insert having the size and shape of a280 size casual shoe last. GORE-SEAM® tape (commercially available fromW.L. Gore and Associates Inc., Elkton, Md.) was then applied to thestitched seams to form a waterproof seam over the stitched seams of theshoe insert. The shoe insert was then placed on the 280 size shoe lastwhich formed a reasonable fit around the last, although wrinkles andexcess material were observed.

The shoe insert was then removed from the last and attached to theleather upper materials of the casual shoe by stitching the shoe insertto the collar portion of the upper. The upper materials and stitchedliner were then repositioned onto the 280 size casual shoe last and asolvent based chloroprene rubber adhesive was placed on the heel and toeareas (8250 supplied by Henkel Technologies Korea, 604-030, 472Shinpyung-Dong, Saha-Ku, Busan, Korea) and sole area (8700H supplied byHenkel Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan,Korea).

A protective EVA layer (2.0 mm, hardness 55 supplied by Dong Bo S.M.Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan, Korea) was adhered to theinsole board (A TEX 6331+Blue Tex supplied by Dong Bo S.M. Co., Ltd#520-36 Gouebob-dong Sang-Gu, Busan, Korea) using a solvent basedchloroprene rubber adhesive (8700H supplied by Henkel TechnologiesKorea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea). The EVAprotective layer was then attached to the sole of the shoe insert. Theupper materials were then lasted around the shoe insert and attachedinsole board. Finally, a rubber sole was attached to the insole of theliner using a solvent based polyurethane adhesive (6190S, part numberZY30204093, commercially available from Henkel Technologies Korea,604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea) to complete the shoeconstruction.

Selected shoes were then tested for water vapor permeability(breathability) using the Whole Boot Water Vapor Permeability testmethod outlined above in the whole boot moisture vapor transmission ratetest. The average water vapor permeability was determined to be 6.5g/hr.

The selected shoes were then tested for waterproofness according to theCentrifuge Test for Waterproofness described above. The selectedfootwear met the waterproofness standard, showing no water leaks after30 min.

Basic hand assessment of the surface characteristics of the inner shoeto assess the degree of the fit of the shoe insert showed thatsignificant folds, wrinkles, or seams were present, especially in thetoe areas, which would be expected to compromise comfort fitcharacteristics of the shoes. Utilizing 3D scanning equipment, images ofthe shoe cross section at various positions along the shoe length werecaptured. FIG. 7 depicts a schematic illustration of a typicalcross-sectional image at a position 3 cm from the end of the shoe toearea. As shown in FIG. 7, the polytetrafluoroethylene-based shoe insert110 showed a relatively poor fit to the upper leather materials 90 withevidence of significant folds and large air spaces 120 between the shoeinsert 110 and upper materials 90.

To better illustrate the fit during use, additional 3D scans were takenwith an artificial foot insert 100 of the appropriate size. A schematicdepiction of a typical scan of a cross-section of the shoe with theartificial shoe insert 100 is depicted in FIG. 8, clearly highlighting asignificant number of contacts or interactions between the shoe insert110 and foot insert 100, which would be expected to compromise comfortfit.

Example 7

A waterproof woman's casual shoe was made with natural split suedeleather upper materials suitable for a casual shoe (part numberJS120130501, commercially available from J. S. IND Co., Ltd. #1086-9,Janglim-Dong, Saha-Ku, Busan, Korea).. The upper materials were stitchedtogether to form the upper of the waterproof casual shoe. A 0.6 mm toepuff (part number TFL060, commercially available from Han Young IndustryCo., Ltd, #394-5 Samrak-dong Sasang-Gu, Busan, Korea) and a 1.7 mmleather board heel counter (supplied by Young Poly Chemical Co. Ltd.#907-7 Manduck 3-dong Buk-Gu, Busan, Korea. Liner materials) wereattached to the upper of the shoe.

A 3-layer bootie was produced in the same manner as Example 1. The3-layer bootie was then thermally formed by loosely placing the bootieonto a conventional ladies 230 size casual shoe asymmetrical last andheating the bootie and last in an air circulating oven at 140° C. for 30min. During this thermal dwell, the bootie closely formed to the shapeand size of the conventional, asymmetrical last, thereby forming asmooth and close fitting shoe insert to the last. The last was removedfrom the oven and allowed to cool to less than 50° C., after which theshoe insert was removed from the conventional, asymmetric last.

During shoe production, the shaped shoe insert was placed on the 230size casual shoe last to form a smooth and close fit around the lastwith no seams, noticeable wrinkles, or excess material. The shoe insertwas then cut and trimmed around the heel collar area to ensure the shoeinsert pattern was correctly sized.

The shoe insert was then removed from the last and attached to theleather upper materials of the casual shoe by stitching the shoe insertto the collar portion of the upper. The upper materials and stitchedliner were then repositioned onto the 230 size casual shoe last and asolvent based chloroprene rubber adhesive was placed on the heel and toeareas (8250 supplied by Henkel Technologies Korea, 604-030, 472Shinpyung-Dong, Saha-Ku, Busan, Korea) and sole (8700H supplied byHenkel Technologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan,Korea). A protective EVA layer (2.0 mm, hardness 55 supplied by Dong BoS.M. Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan, Korea) was adhered tothe insole board (A TEX 6331 supplied by Dong Bo S.M. Co., Ltd #520-36Gouebob-dong Sang-Gu, Busan, Korea) using a solvent based chloroprenerubber adhesive (8700H supplied by Henkel Technologies Korea, 604-030,472 Shinpyung-Dong, Saha-Ku, Busan, Korea). The EVA protective layer wasthen attached to the sole of the shoe insert. The upper materials werethen lasted around the shoe insert and attached insole board. Finally, arubber sole was attached to the insole of the shoe insert using asolvent based polyurethane adhesive (6190S, part number ZY30204093,commercially available from Henkel Technologies Korea, 604-030, 472Shinpyung-Dong, Saha-Ku, Busan, Korea) to complete the shoeconstruction.

Selected shoes were then tested for water vapor permeability(breathability) using the Whole Boot Water Vapor Permeability testmethod outlined above in the whole boot moisture vapor transmission ratetest. The average water vapor permeability was determined to be 3.5g/hr.

The selected shoes were then tested for waterproofness according to theCentrifuge Test for Waterproofness described above. The selectedfootwear met the waterproofness standard, showing no water leaks after30 min.

Basic hand assessment of the surface characteristics of the inner shoeto assess the degree of the fit of the shoe insert showed that no folds,wrinkles or seams were present to compromise comfort fit characteristicsof the shoes.

Comparative Example 4

Women's casual shoes were made with natural split suede leather uppermaterials suitable for a casual shoe (part number JS120130501,commercially available from J. S. IND Co., Ltd. #1086-9, Janglim-Dong,Saha-Ku, Busan, Korea). The upper materials were stitched together toform the upper of the casual shoes. A 0.6 mm toe puff (part numberTFL060, commercially available from Han Young Industry Co., Ltd, #394-5Samrak-dong Sasang-Gu, Busan, Korea) and a 1.7 mm leather board heelcounter (supplied by Young Poly Chemical Co. Ltd. #907-7 Manduck 3-dongBuk-Gu, Busan, Korea) were then attached to the upper of the shoe.

A shoe insert made of a laminate of expanded polytetrafluoroethylene anda textile (part number VISI001001B, commercially available from W.L.Gore and Associates Inc., Elkton, Md.), The laminate was cut andstitched together to form a shoe insert having the size and shape of a230 size casual shoe last. GORE-SEAM® tape (commercially available fromW.L. Gore and Associates Inc., Elkton, Md.) was then applied to thestitched seams to form a waterproof seam over the stitched seams of theshoe insert. The shoe insert was then placed on the 230 size casual shoelast which formed a reasonable fit around the last, although wrinklesand excess material were observed.

The liner was removed from the casual shoe last and attached to theleather upper materials of the casual shoe by stitching the liner to thecollar portion of the upper. The upper materials and stitched liner werethen repositioned onto the 230 size casual shoe last and a solvent basedchloroprene rubber adhesive was placed on the heel and toe areas (8250supplied by Henkel Technologies Korea, 604-030, 472 Shinpyung-Dong,Saha-Ku, Busan, Korea) and sole area (8700H supplied by HenkelTechnologies Korea, 604-030, 472 Shinpyung-Dong, Saha-Ku, Busan, Korea).

A protective EVA layer (2.0 mm, hardness 55 supplied by Dong Bo S.M.Co., Ltd #520-36 Gouebob-dong Sang-Gu, Busan, Korea) was adhered to theinsole board (A TEX 6331 supplied by Dong Bo S.M. Co., Ltd #520-36Gouebob-dong Sang-Gu, Busan, Korea) using the solvent based chloroprenerubber adhesive (8700H supplied by Henkel Technologies Korea, 604-030,472 Shinpyung-Dong, Saha-Ku, Busan, Korea). The EVA protective layer wasthen attached to the sole of the shoe insert. The upper materials werethen lasted around the shoe insert and attached insole board. Finally, arubber sole was attached to the insole of the shoe insert using asolvent based polyurethane adhesive (6190S, part number ZY30204093),commercially available from Henkel Technologies Korea, 604-030, 472Shinpyung-Dong, Saha-Ku, Busan, Korea) to complete the shoeconstruction.

Selected shoes were then tested for water vapor permeability(breathability) using the Whole Boot Water Vapor Permeability testmethod outlined above in the whole boot moisture vapor transmission ratetest. The average water vapor permeability was determined to be 3.6g/hr.

The selected shoes were then tested for waterproofness according to theCentrifuge Test for Waterproofness described above. The selectedfootwear met the waterproofness standard showing, no water leaks after30 min.

Basic hand assessment of the surface characteristics of the inner shoeto assess the degree of fit of the shoe insert showed that significantfolds, wrinkles and seams were present, especially in the toe areas thatwould be expected to compromise comfort fit characteristics of theshoes.

Example 8

A symmetrical nylon foot last was fixed onto a clamp which can berotated through an angle of approximately 140° using a pneumaticcylinder. A polyurethane adhesive web (UT8, 20 g/m² polyurethanenon-woven hot melt adhesive obtained from Protechnic, 41 AvenueMontaigne, F-68700, Cernay, France) was applied to one side of acommercially available men's dress sock of 65% spun silk and 35%polyamide (Windsor Collection Dress Sock Large available throughAmazon.com) using a heat press set at 130° C. and effective pressure of34 psi. It was noted that the sock construction had heel and toe areasreinforced with additional, thicker material. In addition to the heeland toe reinforcement, the sock had an angled heel which produced a morefoot-like shape. The sock with the polyurethane adhesive web thereon waspositioned tightly over the last. The sock was applied to the last withthe adhesive web exposed on the outer surface of the last. Care wastaken when applying the sock to the last to avoid wrinkles.

A portion of the expanded PTFE tape produced in Example 1 having alength of approximately 1 meter and a width of approximately 7.4 cm wasobtained and fixed in a frame by placing the tape edges between sixtoggle clamps positioned along each tape edge and compressing the PTFEtape between two rubber seals. To ensure that the width of the taperemained fixed, each tape edge and clamp assembly was fixed to the frameusing locking nuts. The secured tape in the frame had a width of 6.9 cm.The PTFE tape fixed in the frame was then heated using an industrial airheater for approximately 20 seconds during which the tape reached atemperature of 40-50° C. The locking nuts were then released and theedges of the tape were slowly, manually moved apart slowly in the widthdirection until the tape was expanded to a width of 37.1 cm. To preventshrink back of the tape and to maintain the tape width, the frame edgeswere then secured again using the locking nuts.

After the tape was expanded in the width direction and secured using thelocking nuts, the tape was then heated using the industrial hand heldair heater, during which the tape reached a temperature of approximately70° C.

The frame containing the expanded PTFE tape was then removed from theheat and positioned above the symmetrical last. The pneumatic cylinderwas then activated to allow the symmetrical last having thereon the sockand adhesive to rotate upwardly at an angle of 90° to penetrate anddeform the preheated PTFE tape around the last. The final deformation ofthe tape was completed by hand to ensure that the tape was deformedclosely to the shape of the last and to minimize wrinkles.

A second commercially available commercially available men's dress sockof 65% spun silk and 35% polyamide (Windsor Collection Dress Sock Largeavailable through Amazon.com) having thereon a polyurethane adhesive web(UT8, 20 g/m² polyurethane non-woven hot melt adhesive obtained fromProtechnic, 41 Avenue Montaigne, F-68700, Cernay, France) was thenplaced over the deformed PTFE tape with the polyurethane adhesivepositioned in direct contact with the surface of the deformed expandedPTFE. Care was taken to minimize wrinkling of the PTFE tape and thesock.

The 3-layer article (sock/deformed expanded PTFE tape/sock) was thensecured at the collar of the last using an elastomeric retaining band toprevent further movement. The complete assembly of the 3-layer articleand nylon last was then placed in an oven set at 140° C. for a time of30 min. During this thermal dwell, the last reached an approximatetemperature of 110° C. The assembly was then removed and a vacuum bagwas quickly applied over the assembly. A vacuum was applied at 27 inchesHg until the assembly had cooled to approximately 50° C. to ensure goodcontact between the three layers and subsequent adhesive bonding betweenthe socks and expanded PTFE tape layer. The vacuum was then removed fromthe assembly. The vacuum bag and elastomeric retaining band were thenremoved from the last and the completed 3-layer bootie was slowlyremoved from the last.

The 3-layer bootie was then tested for water vapor permeability(breathability) using the Whole Boot Water Vapor Permeability testmethod outlined above in the moisture vapor transmission rate. Theaverage water vapor permeability was determined to be 16.5 g/hr.

The 3-layer shoe insert was then tested for waterproofness according tothe Modified Centrifuge Test for waterproofness described above. Theselected footwear met the waterproofness standard, showing no waterleaks after 60 min.

Example 9

A 3-layer bootie was prepared as outlined above in Example 8 and thenthermally formed by loosely placing the bootie onto a men's 265 sizerunning shoe last and then placing the bootie in an air circulating ovenat 140° C. for 30 min. During this thermal dwell, the liner closelyformed to the shape and size of the last, forming a smooth and closefitting shoe insert to that of the running show last, particularly inthe heel area up to the ankle height of the shoe. FIG. 9 is a schematicillustration depicting the shoe insert (dotted lines) on the runningshoe last after the shoe insert was shaped. The last was removed fromthe oven and allowed to cool to less than 50° C., after which the linerwas removed from the last.

The 3-layer bootie was tested for water vapor permeability(breathability) using the Whole Boot Water Vapor Permeability testmethod outlined above in the moisture vapor transmission rate test andwith the expanded membrane layer being exposed on the upper surface. Theaverage water vapor permeability was determined to be 19.6 g/hr.

The 3-layer bootie was then tested for waterproofness according to theModified Centrifuge Test for Waterproofness described above. Theselected footwear met the waterproofness standard showing no water leaksafter 60 min.

Example 10

A symmetrical aluminum foot last was fixed onto a clamp which can berotated through an angle of approximately 140° using a pneumaticcylinder. An expanded PTFE tape made generally in accordance with theteachings set forth in U.S. Pat. No. 7,306,729 to Bacino, et al. havinga length of approximately 1 meter and a width of approximately 7.4 cmwas fixed in a frame by placing the edges of the tape between six toggleclamps positioned along the tape edges and compressing the tape betweentwo rubber seals. To ensure that the width of the tape remained fixed,the tape edges and clamp assembly were fixed to the frame using lockingnuts. The secured tape in the frame had a width of 6.9 cm.

The tape fixed in the frame was then heated using an industrial airheater for approximately 20 seconds during which the tape reached atemperature of 40-50° C. The locking nuts were then released and theedges of the tape were slowly manually moved apart in the widthdirection until the tape was expanded to a width of 37.1 cm. To preventshrink back of the tape and to maintain the tape width, the frame edgeswere again secured using the locking nuts. After the tape was expandedin the width direction and secured using the locking nuts, the ePTFEtape was heated using the industrial air heater during which the tapereached a temperature of approximately 70° C.

The frame containing the ePTFE tape was then removed from the heat andpositioned above the symmetrical last. The pneumatic cylinder was thenactivated to allow the symmetrical to rotate upwardly at an angle of 90°to penetrate and deform the preheated PTFE tape around the last. Thefinal deformation of the tape over the last was completed by hand toensure that the tape was deformed closely to the shape of the last andto minimize wrinkles.

The symmetrical last and deformed expanded PTFE were then placed in anoven at 365° C. for 20 minutes to ensure that the expanded PTFE was“amorphously-locked”. The complete assembly was then removed from theoven and left to cool to room temperature.

After cooling, a polyurethane adhesive web (UT8, 20 g/m² polyurethanenon-woven hot melt adhesive obtained from Protechnic, 41 AvenueMontaigne, F-68700, Cernay, France) was applied to one side of acommercially available men's black sock of 60 den (66 dtex) 61%polyamide, 37% cotton and 2% elastane (Sockchen Naturelle 60commercially available from Nur Die GmbH, Rheine, Germany) using a heatpress set at 130° C. and effective pressure of 5 psi. The sock with thepolyurethane adhesive web thereon was positioned tightly over the lastwith the adhesive web in direct contact with the ePTFE surface. Care wastaken when applying the sock to the last to avoid wrinkles,

The 2-layer article (sock-deformed expanded PTFE) was then secured atthe collar of the last using an elastomeric retaining band to preventfurther movement. The complete assembly of the 2-layer article andaluminum last was then placed in an oven set at 140° C. for 45 min. Theassembly was then removed and a vacuum bag was quickly applied over theassembly. A vacuum was applied at 27 inches Hg until the assembly hadcooled to approximately 50° C. to ensure good contact between the layersand bonding between the sock and ePTFE layer. The vacuum was thenremoved from the assembly. The vacuum bag and elastomeric retaining bandwere removed from the last. Finally, the completed 2-layer bootie wasslowly and carefully removed from the last.

Example 11

A symmetrical nylon foot last was fixed onto a clamp which can berotated through an angle of approximately 140° using a pneumaticcylinder. A polyurethane adhesive web (UT8, 20 g/m² polyurethanenon-woven hot melt adhesive obtained from Protechnic, 41 AvenueMontaigne, F-68700, Cernay, France) was applied to one side of acommercially available 60 den (66 dtex) 61% polyamide, 37% cotton and 2%elastane black sock (Sockchen Naturelle 60 commercially available fromNur Die GmbH, Rheine, Germany) using a heat press set at 130° C. andeffective pressure of 5 psi. The sock was applied to a symmetrical lastwith the adhesive web exposed on the outer surface of the symmetricallast. Care was taken when applying the sock to the last to avoidwrinkles.

A fine powder of PTFE polymer (Daiken Industries, Ltd., Orangeburg,N.Y.) was blended with Isopar® K (Exxon Mobil Corp., Fairfax, Va.) inthe proportion of 0.196 g/g of fine powder. The lubricated powder wascompressed in a cylinder to form a pellet and placed into an oven set at70° C. for approximately 12 hours. Compressed and heated pellets wereram extruded to produce tapes approximately 15.2 cm wide by 0.73 mmthick. Three separate rolls of tape were produced and layered togetherbetween compression rolls to a thickness of 0.76 cm. The tape was thentransversely stretched to 56 cm (i.e., at a ratio of 3.7:1), restrained,and then dried in an oven set at 270° C. The dry tape was longitudinallyexpanded between banks of rolls over a heated plate set to a temperatureof 340° C. The speed ratio between the second bank of rolls and thefirst bank of rolls, and hence the expansion ratio, was 8:1.

A portion of the expanded PTFE tape having a length of approximately 1meter and a width of approximately 12.5 cm was fixed in a frame byplacing the tape edges between six toggle clamps positioned along eachtape edge and compressing the tape between two rubber seals. To ensurethat the width remained fixed, the tape edges and the clamp assemblywere fixed to the frame using locking nuts. The secured tape in theframe had a width of 9 cm.

The tape fixed in the frame was then heated using an industrial airheater for approximately 20 seconds, during which the tape reached atemperature of 40-50° C. The locking nuts were then released and theedges of the tape were slowly, manually moved apart in the widthdirection until the tape was expanded to a width of 27 cm. To preventshrink back of the tape and to maintain the 27 cm tape width, the frameedges were again secured using the locking nuts.

After the tape was expanded in the width direction and secured using thelocking nuts, the tape was then heated using the industrial air heater,during which the tape reached a temperature of approximately 70° C. Thepneumatic cylinder was then activated to allow the symmetrical lasthaving thereon the sock and adhesive to rotate upwardly at an angle of90° to penetrate and deform the preheated PTFE tape around the last. Thefinal deformation of the tape over the last was completed by hand toensure that the tape deformed closely to the shape of the last and tominimize wrinkles.

A second sock (60 den (66 dtex) 61% polyamide, 37% cotton and 2%elastane black sock (Sockchen Naturelle 60 commercially available fromNur Die GmbH, Rheine, Germany) having thereon a polyurethane adhesiveweb was then placed over the deformed tape with the adhesive positionedin direct contact with the surface of the deformed expanded PTFE tape.Care was taken when applying the sock to minimize wrinkling.

The 3-layer article (sock/deformed expanded PTFE tape/sock) was thensecured at the collar of the last using an elastomeric retaining band toprevent further movement. The complete assembly of the 3-layer articleand nylon last was then placed in an oven at 150° C. for 30 min. Duringthis thermal dwell, the last reached an approximate temperature of 120°C. The assembly was then removed and a vacuum bag was quickly appliedover the assembly. A vacuum was applied (at 27 inches Hg) until theassembly had cooled to approximately 50° C. to ensure good contactbetween the layers and subsequent adhesive bonding between the socks andexpanded PTFE layer. The vacuum was then removed from the assembly andthe vacuum bag removed. The elastomeric retaining band was removed fromthe last and the completed sock is slowly removed from the last. Thesock has a high degree of elasticity and can be subsequently stretchedto form a close fitting sock over a broad range of last sizes, such as,for example, a ladies medium (e.g. EU size 240) to a men's large (e.g.,EU size 275).

The sock was then tested for water vapor permeability (breathability)using the Sock Water Vapor Permeability test method outlined above. Theaverage sock water vapor permeability was determined to be 26.4 g/hr.

When the sock was placed in a running shoe, the water vapor permeabilityof the shoe and sock was determined to be 11.7 g/hr.

Selected shoes were then tested for waterproofness according to theCentrifuge Test for Waterproofness described above. The selectedfootwear met the waterproofness standard, showing no water leaks after60 min.

Comparative Example 5

A 275 sized shoe insert made of a laminate of expandedpolytetrafluoroethylene and a textile (part number VISI001001B,commercially available from W.L. Gore and Associates Inc., Elkton, Md.)was produced utilizing conventional means. Specifically, the laminatewas cut and stitched together to form the 275 sized sock insert.GORE-SEAM® tape (commercially available from W.L. Gore and AssociatesInc., Elkton, Md.) was then applied to the stitched seams to form awaterproof seam over the stitched seams of the insert. The sock insertwas then tested for water vapor permeability (breathability) using theSock Water Vapor Permeability test method outlined above. The averagesock insert water vapor permeability was determined to be 17.7 g/hr.

The sock was then tested for waterproofness according to the CentrifugeTest for Waterproofness described above. The sock met the waterproofnessstandard, showing no water leaks after 60 min.

Comparative Example 6

For comparative water vapor transmission rate and waterproofnesstesting, a commercially available large size waterproof and breathablesock was obtained (Seal Skinz Thin Socklet from Seal Skinz Ltd, 36Oldmedow Road, Norfolk, PE30 3PP, United Kingdom).

The sock was tested for water vapor permeability (breathability) usingthe test method outlined above in the sock moisture vapor transmissionrate test. The average sock water vapor permeability was determined at11.8 g/hr. When the sock was placed in a running shoe, the water vaporpermeability of the shoe and sock was determined to be 6.6 g/hr.

The sock was then tested for waterproofness according to the CentrifugeTest for Waterproofness described above. The sock did not meet thewaterproofness standard showing water leaks after 15 minutes.

The invention of this application has been described above bothgenerically and with regard to specific embodiments. Although theinvention has been set forth in what is believed to be the preferredembodiments, a wide variety of alternatives known to those of skill inthe art can be selected within the generic disclosure. The invention isnot otherwise limited, except for the recitation of the claims set forthbelow.

What is claimed is:
 1. A last comprising: a symmetrical shaped formhaving generally the shape of a foot having a sole region, a toe region,a heel region and a protruded gusset region.
 2. The last of claim 1,wherein said last comprises a multi-part last.
 3. The last of claim 1,wherein said last comprises a two-part last, the last comprising a firstpart having the shape of a conventional last and a second partcomprising a protruded gusset region which is separable from said firstpart.
 4. A sock comprising a protruded gusset region.